Move most of the remaining USD/PSD/SMM papers into share/doc

24 files changed, 9915 insertions, 4 deletions

diff --git a/share/doc/usd/04.csh/Makefile b/share/doc/usd/04.csh/Makefile
index d22a7b9..5606b8f 100644
--- a/share/doc/usd/04.csh/Makefile
+++ b/share/doc/usd/04.csh/Makefile
@@ -5,6 +5,5 @@ VOLUME=		usd/04.csh
 SRCS=		tabs csh.1 csh.2 csh.3 csh.4 csh.a csh.g
 MACROS=		-ms
 USE_SOELIM=
-SRCDIR=		${.CURDIR}/../../../../bin/csh/USD.doc
 
 .include <bsd.doc.mk>
diff --git a/share/doc/usd/04.csh/csh.1 b/share/doc/usd/04.csh/csh.1
new file mode 100644
index 0000000..915cb23
--- /dev/null
+++ b/share/doc/usd/04.csh/csh.1
@@ -0,0 +1,1012 @@
+.\"-
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)csh.1	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.EH 'USD:4-%''An Introduction to the C shell'
+.OH 'An Introduction to the C shell''USD:4-%'
+.\".RP
+.TL
+An Introduction to the C shell
+.AU
+William Joy
+(revised for 4.3BSD by Mark Seiden)
+.AI
+Computer Science Division
+.br
+Department of Electrical Engineering and Computer Science
+.br
+University of California, Berkeley
+.br
+Berkeley, California 94720
+.AB
+.I Csh
+is a new command language interpreter for
+.UX
+systems.
+It incorporates good features of other shells and a
+.I history
+mechanism similar to the
+.I redo
+of \s-2INTERLISP\s0.
+While incorporating many features of other shells which make
+writing shell programs (shell scripts) easier,
+most of the features unique to
+.I csh
+are designed more for the interactive \s-2UNIX\s0 user.
+.PP
+\s-2UNIX\s0
+users who have read a general introduction to the system
+will find a valuable basic explanation of the shell here.
+Simple terminal interaction with
+.I csh
+is possible after reading just the first section of this document.
+The second section describes the shell's capabilities which you can
+explore after you have begun to become acquainted with the shell.
+Later sections introduce features which are useful, but not necessary
+for all users of the shell.
+.PP
+Additional information includes an appendix listing special characters of the shell
+and a glossary of terms and commands introduced in this manual.
+.AE
+.SH
+.if n .ND
+Introduction
+.PP
+A
+.I shell
+is a command language interpreter.
+.I Csh
+is the name of one particular command interpreter on
+\s-2UNIX\s0.
+The primary purpose of
+.I csh
+is to translate command lines typed at a terminal into
+system actions, such as invocation of other programs.
+.I Csh
+is a user program just like any you might write.
+Hopefully,
+.I csh
+will be a very useful program for you
+in interacting with the \s-2UNIX\s0 system.
+.PP
+In addition to this document, you will want to refer to a copy
+of the \s-2UNIX\s0 User Reference Manual.
+The
+.I csh
+documentation in section 1 of the manual provides a full description of all
+features of the shell and is the definitive reference for questions
+about the shell.
+.PP
+Many words in this document are shown in
+.I italics.
+These are important words;
+names of commands, and words which have special meaning in discussing
+the shell and \s-2UNIX\s0.
+Many of the words are defined in a glossary at the end of this document.
+If you don't know what is meant by a word, you should look
+for it in the glossary.
+.SH
+Acknowledgements
+.PP
+Numerous people have provided good input about previous versions
+of
+.I csh
+and aided in its debugging and in the debugging of its documentation.
+I would especially like to thank Michael Ubell
+who made the crucial observation that history commands could be
+done well over the word structure of input text, and implemented
+a prototype history mechanism in an older version of the shell.
+Eric Allman has also provided a large number of useful comments on the
+shell, helping to unify those concepts which are present and to identify
+and eliminate useless and marginally useful features.
+Mike O'Brien suggested the pathname hashing
+mechanism which speeds command execution.
+Jim Kulp added the job control and directory stack primitives and
+added their documentation to this introduction.
+.br
+.bp
+.NH
+Terminal usage of the shell
+.NH 2
+The basic notion of commands
+.PP
+A
+.I shell
+in
+\s-2UNIX\s0
+acts mostly as a medium through which other
+.I programs
+are invoked.
+While it has a set of
+.I builtin
+functions which it performs directly,
+most commands cause execution of programs that are, in fact,
+external to the shell.
+The shell is thus distinguished from the command interpreters of other
+systems both by the fact that it is just a user program, and by the fact
+that it is used almost exclusively as a mechanism for invoking other programs.
+.PP
+.I Commands
+in the \s-2UNIX\s0 system consist of a list of strings or
+.I words
+interpreted as a
+.I "command name"
+followed by
+.I arguments.
+Thus the command
+.DS
+mail bill
+.DE
+consists of two words.
+The first word
+.I mail
+names the command to be executed, in this case the
+mail program which sends messages to other users.
+The shell uses the name of the command in attempting to execute it for you.
+It will look in a number of
+.I directories
+for a file with the name
+.I mail
+which is expected to contain the mail program.
+.PP
+The rest of the words of the command are given as
+.I arguments
+to the command itself when it is executed.
+In this case we specified also the argument
+.I bill
+which is interpreted by the
+.I mail
+program to be the name of a user to whom mail is to be sent.
+In normal terminal usage we might use the
+.I mail
+command as follows.
+.DS
+% mail bill
+I have a question about the csh documentation.
+My document seems to be missing page 5.
+Does a page five exist?
+	Bill
+EOT
+%
+.DE
+.PP
+Here we typed a message to send to
+.I bill
+and ended this message with a ^D which sent an end-of-file to
+the mail program.
+(Here and throughout this document, the notation ``^\fIx\fR''
+is to be read ``control-\fIx\fR'' and represents the striking of the \fIx\fR
+key while the control key is held down.)
+The mail program
+then echoed the characters `EOT' and transmitted our message.
+The characters `% ' were printed before and after the mail command
+by the shell to indicate that input was needed.
+.PP
+After typing the `% ' prompt the shell was reading command input from
+our terminal.
+We typed a complete command `mail bill'.
+The shell then executed the
+.I mail
+program with argument
+.I bill
+and went dormant waiting for it to complete.
+The mail program then read input from our terminal until we signalled
+an end-of-file via typing a ^D after which the shell noticed
+that mail had completed
+and signaled us that it was ready to read from the terminal again by
+printing another `% ' prompt.
+.PP
+This is the essential pattern of all interaction with \s-2UNIX\s0
+through the shell.
+A complete command is typed at the terminal, the shell executes
+the command and when this execution completes, it prompts for a new command.
+If you run the editor for an hour, the shell will patiently wait for
+you to finish editing and obediently prompt you again whenever you finish
+editing.
+.PP
+An example of a useful command you can execute now is the
+.I tset
+command, which sets the default
+.I erase
+and
+.I kill
+characters on your terminal \- the erase character erases the last
+character you typed and the kill character erases the entire line you
+have entered so far.
+By default, the erase character is the delete key (equivalent to `^?')
+and the kill character is `^U'.  Some people prefer to make the erase character
+the backspace key (equivalent to `^H').
+You can make this be true by typing
+.DS
+tset \-e
+.DE
+which tells the program
+.I tset
+to set the erase character to tset's default setting for this character
+(a backspace).
+.NH 2
+Flag arguments
+.PP
+A useful notion in \s-2UNIX\s0 is that of a
+.I flag
+argument.
+While many arguments to commands specify file names or user names,
+some arguments rather specify an optional capability of the command
+which you wish to invoke.
+By convention, such arguments begin with the character `\-' (hyphen).
+Thus the command
+.DS
+ls
+.DE
+will produce a list of the files in the current
+.I "working directory" .
+The option
+.I \-s
+is the size option, and
+.DS
+ls \-s
+.DE
+causes
+.I ls
+to also give, for each file the size of the file in blocks of 512
+characters.
+The manual section for each command in the \s-2UNIX\s0 reference manual
+gives the available options for each command.
+The
+.I ls
+command has a large number of useful and interesting options.
+Most other commands have either no options or only one or two options.
+It is hard to remember options of commands which are not used very
+frequently, so most \s-2UNIX\s0 utilities perform only one or two functions
+rather than having a large number of hard to remember options.
+.NH 2
+Output to files
+.PP
+Commands that normally read input or write output on the terminal
+can also be executed with this input and/or output done to
+a file.
+.PP
+Thus suppose we wish to save the current date in a file called `now'.
+The command
+.DS
+date
+.DE
+will print the current date on our terminal.
+This is because our terminal is the default
+.I "standard output"
+for the date command and the date command prints the date on its
+standard output.
+The shell lets us
+.I redirect
+the
+.I "standard output"
+of a command through a
+notation using the
+.I metacharacter
+`>' and the name of the file where output is to be placed.
+Thus the command
+.DS
+date > now
+.DE
+runs the
+.I date
+command such that its standard output is
+the file `now' rather than the terminal.
+Thus this command places the current date and time into the file `now'.
+It is important to know that the
+.I date
+command was unaware that its output was going to a file rather than
+to the terminal.
+The shell performed this
+.I redirection
+before the command began executing.
+.PP
+One other thing to note here is that the file `now'
+need not have existed before the
+.I date
+command was executed; the shell would have created the file if it did
+not exist.
+And if the file did exist?
+If it had existed previously these previous contents would have been discarded!
+A shell option
+.I noclobber
+exists to prevent this from happening accidentally;
+it is discussed in section 2.2.
+.PP
+The system normally keeps files which you create with `>' and all other files.
+Thus the default is for files to be permanent.  If you wish to create a file
+which will be removed automatically, you can begin its name with a `#'
+character, this `scratch' character denotes the fact that the file will
+be a scratch file.*
+.FS
+*Note that if your erase character is a `#', you will have to precede the
+`#' with a `\e'.  The fact that the `#' character is the old (pre-\s-2CRT\s0)
+standard erase character means that it seldom appears in a file name, and
+allows this convention to be used for scratch files.  If you are using a
+\s-2CRT\s0, your erase character should be a ^H, as we demonstrated
+in section 1.1 how this could be set up.
+.FE
+The system will remove such files after a couple of days,
+or sooner if file space becomes very tight.
+Thus, in running the
+.I date
+command above, we don't really want to save the output forever, so we
+would more likely do
+.DS
+date > #now
+.DE
+.NH 2
+Metacharacters in the shell
+.PP
+The shell has a large number of
+special characters (like `>')
+which indicate special functions.
+We say that these notations have
+.I syntactic
+and
+.I semantic
+meaning to the shell.
+In general, most characters which are neither letters nor digits
+have special meaning to the shell.
+We shall shortly learn a means of
+.I quotation
+which allows us to use
+.I metacharacters
+without the shell treating them in any special way.
+.PP
+Metacharacters normally have effect only when the shell is reading
+our input.
+We need not worry about placing shell metacharacters in a letter
+we are sending via
+.I mail,
+or when we are typing in text or data to some other program.
+Note that the shell is only reading input when it has prompted with
+`% ' (although we can type our input even before it prompts).
+.NH 2
+Input from files; pipelines
+.PP
+We learned above how to
+.I redirect
+the
+.I "standard output"
+of a command
+to a file.
+It is also possible to redirect the
+.I "standard input"
+of a command from a file.
+This is not often necessary since most commands will read from
+a file whose name is given as an argument.
+We can give the command
+.DS
+sort < data
+.DE
+to run the
+.I sort
+command with standard input, where the command normally
+reads its input, from the file
+`data'.
+We would more likely say
+.DS
+sort data
+.DE
+letting the
+.I sort
+command open the file
+`data'
+for input itself since this is less to type.
+.PP
+We should note that if we just typed
+.DS
+sort
+.DE
+then the sort program would sort lines from its
+.I "standard input."
+Since we did not
+.I redirect
+the standard input, it would sort lines as we typed them on the terminal
+until we typed a ^D to indicate an end-of-file.
+.PP
+A most useful capability is the ability to combine the standard output
+of one command with the standard input of another, i.e. to run the
+commands in a sequence known as a
+.I pipeline.
+For instance the command
+.DS
+ls \-s
+.DE
+normally produces a list of the files in our directory with the size
+of each in blocks of 512 characters.
+If we are interested in learning which of our files is largest we
+may wish to have this sorted by size rather than by name, which is
+the default way in which
+.I ls
+sorts.
+We could look at the many options of
+.I ls
+to see if there was an option to do this but would eventually discover
+that there is not.
+Instead we can use a couple of simple options of the
+.I sort
+command, combining it with
+.I ls
+to get what we want.
+.PP
+The
+.I \-n
+option of sort specifies a numeric sort rather than an alphabetic sort.
+Thus
+.DS
+ls \-s | sort \-n
+.DE
+specifies that the output of the
+.I ls
+command run with the option
+.I \-s
+is to be
+.I piped
+to the command
+.I sort
+run with the numeric sort option.
+This would give us a sorted list of our files by size, but with the
+smallest first.
+We could then use the
+.I \-r
+reverse sort option and the
+.I head
+command in combination with the previous command doing
+.DS
+ls \-s | sort \-n \-r | head \-5
+.DE
+Here we have taken a list of our files sorted alphabetically,
+each with the size in blocks.
+We have run this to the standard input of the
+.I sort
+command asking it to sort numerically in reverse order (largest first).
+This output has then been run into the command
+.I head
+which gives us the first few lines.
+In this case we have asked
+.I head
+for the first 5 lines.
+Thus this command gives us the names and sizes of our 5 largest files.
+.PP
+The notation introduced above is called the
+.I pipe
+mechanism.
+Commands separated by `\||\|' characters are connected together by the
+shell and the standard output of each is run into the standard input of the
+next.
+The leftmost command in a pipeline will normally take its standard
+input from the terminal and the rightmost will place its standard
+output on the terminal.
+Other examples of pipelines will be given later when we discuss the
+history mechanism;
+one important use of pipes which is illustrated there is in the
+routing of information to the line printer.
+.NH 2
+Filenames
+.PP
+Many commands to be executed will need the names of files as arguments.
+\s-2UNIX\s0
+.I pathnames
+consist of a number of
+.I components
+separated by `/'.
+Each component except the last names a directory in which the next
+component resides, in effect specifying the
+.I path
+of directories to follow to reach the file.
+Thus the pathname
+.DS
+/etc/motd
+.DE
+specifies a file in the directory
+`etc'
+which is a subdirectory of the
+.I root
+directory `/'.
+Within this directory the file named is `motd' which stands
+for `message of the day'.
+A
+.I pathname
+that begins with a slash is said to be an
+.I absolute
+pathname since it is specified from the absolute top of the entire
+directory hierarchy of the system (the
+.I root ).
+.I Pathnames
+which do not begin with `/' are interpreted as starting in the current
+.I "working directory" ,
+which is, by default, your
+.I home
+directory and can be changed dynamically by the
+.I cd
+change directory command.
+Such pathnames are said to be
+.I relative
+to the working directory since they are found by starting
+in the working directory and descending to lower levels of directories
+for each
+.I component
+of the pathname.  If the pathname contains no slashes at all then the
+file is contained in the working directory itself and the pathname is merely
+the name of the file in this directory.
+Absolute pathnames have no relation
+to the working directory.
+.PP
+Most filenames consist of a number of alphanumeric characters and
+`.'s (periods).
+In fact, all printing characters except `/' (slash) may appear in filenames.
+It is inconvenient to have most non-alphabetic characters in filenames
+because many of these have special meaning to the shell.
+The character `.' (period) is not a shell-metacharacter and is often used
+to separate the
+.I extension
+of a file name from the base of the name.
+Thus
+.DS
+prog.c prog.o prog.errs prog.output
+.DE
+are four related files.
+They share a
+.I base
+portion of a name
+(a base portion being that part of the name that is left when a trailing
+`.' and following characters which are not `.' are stripped off).
+The file
+`prog.c'
+might be the source for a C program,
+the file `prog.o' the corresponding object file,
+the file
+`prog.errs' the errors resulting from a compilation of the program
+and the file
+`prog.output' the output of a run of the program.
+.PP
+If we wished to refer to all four of these files in a command, we could
+use the notation
+.DS
+prog.*
+.DE
+This expression is expanded by the shell, before the command to which it is
+an argument is executed, into a list of names which begin with `prog.'.
+The character `*' here matches any sequence (including the empty sequence)
+of characters in a file name.
+The names which match are alphabetically sorted and placed in the
+.I "argument list"
+of the command.
+Thus the command
+.DS
+echo prog.*
+.DE
+will echo the names
+.DS
+prog.c prog.errs prog.o prog.output
+.DE
+Note that the names are in sorted order here, and a different
+order than we listed them above.
+The
+.I echo
+command receives four words as arguments, even though we only typed
+one word as an argument directly.
+The four words were generated by
+.I "filename expansion"
+of the one input word.
+.PP
+Other notations for
+.I "filename expansion"
+are also available.
+The character `?' matches any single character in a filename.
+Thus
+.DS
+echo ? \|?? \|???
+.DE
+will echo a line of filenames; first those with one character names,
+then those with two character names, and finally those with three
+character names.
+The names of each length will be independently sorted.
+.PP
+Another mechanism consists of a sequence of characters between `[' and `]'.
+This metasequence matches any single character from the enclosed set.
+Thus
+.DS
+prog.[co]
+.DE
+will match
+.DS
+prog.c prog.o
+.DE
+in the example above.
+We can also place two characters around a `\-' in this notation to denote
+a range.
+Thus
+.DS
+chap.[1\-5]
+.DE
+might match files
+.DS
+chap.1 chap.2 chap.3 chap.4 chap.5
+.DE
+if they existed.
+This is shorthand for
+.DS
+chap.[12345]
+.DE
+and otherwise equivalent.
+.PP
+An important point to note is that if a list of argument words to
+a command (an
+.I "argument list)"
+contains filename expansion syntax, and if this filename expansion syntax
+fails to match any existing file names, then the shell considers this
+to be an error and prints a diagnostic
+.DS
+No match.
+.DE
+and does not execute the command.
+.PP
+Another very important point is that files with the character `.' at the
+beginning are treated specially.
+Neither `*' or `?' or the `[' `]' mechanism will match it.
+This prevents accidental matching of the filenames `.' and `..'
+in the working directory which have special meaning to the system,
+as well as other files such as
+.I \&.cshrc
+which are not normally
+visible.
+We will discuss the special role of the file
+.I \&.cshrc
+later.
+.PP
+Another filename expansion mechanism gives access to the pathname of
+the
+.I home
+directory of other users.
+This notation consists of the character `~' (tilde) followed by another user's
+login name.
+For instance the word `~bill' would map to the pathname `/usr/bill'
+if the home directory for `bill' was `/usr/bill'.
+Since, on large systems, users may have login directories scattered over
+many different disk volumes with different prefix directory names,
+this notation provides a convenient way of accessing the files
+of other users.
+.PP
+A special case of this notation consists of a `~' alone, e.g. `~/mbox'.
+This notation is expanded by the shell into the file `mbox' in your
+.I home
+directory, i.e. into `/usr/bill/mbox' for me on Ernie Co-vax, the UCB
+Computer Science Department VAX machine, where this document was prepared.
+This can be very useful if you have used
+.I cd
+to change to another directory and have found a file you wish to
+copy using
+.I cp.
+If I give the command
+.DS
+cp thatfile ~
+.DE
+the shell will expand this command to
+.DS
+cp thatfile /usr/bill
+.DE
+since my home directory is /usr/bill.
+.PP
+There also exists a mechanism using the characters `{' and `}' for
+abbreviating a set of words which have common parts but cannot
+be abbreviated by the above mechanisms because they are not files,
+are the names of files which do not yet exist,
+are not thus conveniently described.
+This mechanism will be described much later,
+in section 4.2,
+as it is used less frequently.
+.NH 2
+Quotation
+.PP
+We have already seen a number of metacharacters used by the shell.
+These metacharacters pose a problem in that we cannot use them directly
+as parts of words.
+Thus the command
+.DS
+echo *
+.DE
+will not echo the character `*'.
+It will either echo a sorted list of filenames in the
+current
+.I "working directory,"
+or print the message `No match' if there are
+no files in the working directory.
+.PP
+The recommended mechanism for placing characters which are neither numbers,
+digits, `/', `.' or `\-' in an argument word to a command is to enclose
+it with single quotation characters `\'', i.e.
+.DS
+echo \'*\'
+.DE
+There is one special character `!' which is used by the
+.I history
+mechanism of the shell and which cannot be
+.I escaped
+by placing it within `\'' characters.
+It and the character `\'' itself can be preceded by a single `\e'
+to prevent their special meaning.
+Thus
+.DS
+echo \e\'\e!
+.DE
+prints
+.DS
+\'!
+.DE
+These two mechanisms suffice to place any printing character into a word
+which is an argument to a shell command.  They can be combined, as in
+.DS
+echo \e\'\'*\'
+.DE
+which prints
+.DS
+\'*
+.DE
+since the first `\e' escaped the first `\'' and the `*' was enclosed
+between `\'' characters.
+.NH 2
+Terminating commands
+.PP
+When you are executing a command and the shell is
+waiting for it to complete there are several ways
+to force it to stop.
+For instance if you type the command
+.DS
+cat /etc/passwd
+.DE
+the system will print a copy of a list of all users of the system
+on your terminal.
+This is likely to continue for several minutes unless you stop it.
+You can send an
+\s-2INTERRUPT\s0
+.I signal
+to the
+.I cat
+command by typing ^C on your terminal.*
+.FS
+*On some older Unix systems the \s-2DEL\s0 or \s-2RUBOUT\s0 key
+has the same effect. "stty all" will tell you the INTR key value.
+.FE
+Since
+.I cat
+does not take any precautions to avoid or otherwise handle this signal
+the
+\s-2INTERRUPT\s0
+will cause it to terminate.
+The shell notices that
+.I cat
+has terminated and prompts you again with `% '.
+If you hit \s-2INTERRUPT\s0 again, the shell will just
+repeat its prompt since it handles \s-2INTERRUPT\s0 signals
+and chooses to continue to execute commands rather than terminating
+like
+.I cat
+did, which would have the effect of logging you out.
+.PP
+Another way in which many programs terminate is when they get an end-of-file
+from their standard input.
+Thus the
+.I mail
+program in the first example above was terminated when we typed a ^D
+which generates an end-of-file from the standard input.
+The shell also terminates when it gets an end-of-file printing `logout';
+\s-2UNIX\s0 then logs you off the system.
+Since this means that typing too many ^D's can accidentally log us off,
+the shell has a mechanism for preventing this.
+This
+.I ignoreeof
+option will be discussed in section 2.2.
+.PP
+If a command has its standard input redirected from a file, then it will
+normally terminate when it reaches the end of this file.
+Thus if we execute
+.DS
+mail bill < prepared.text
+.DE
+the mail command will terminate without our typing a ^D.
+This is because it read to the end-of-file of our file
+`prepared.text' in which we placed a message for `bill' with an editor program.
+We could also have done
+.DS
+cat prepared.text \||\| mail bill
+.DE
+since the
+.I cat
+command would then have written the text through the pipe to the
+standard input of the mail command.
+When the
+.I cat
+command completed it would have terminated,
+closing down the pipeline
+and the
+.I mail
+command would have received an end-of-file from it and terminated.
+Using a pipe here is more complicated than redirecting input
+so we would more likely use the first form.
+These commands could also have been stopped by sending an \s-2INTERRUPT\s0.
+.PP
+Another possibility for stopping a command is to suspend its execution
+temporarily, with the possibility of continuing execution later.  This is
+done by sending a \s-2STOP\s0 signal via typing a ^Z.
+This signal causes all commands running on the terminal
+(usually one but more if a pipeline is executing) to become suspended.
+The shell notices that the command(s) have been suspended, types
+`Stopped' and then prompts for a new command.
+The previously executing command has been suspended, but otherwise
+unaffected by the \s-2STOP\s0 signal.  Any other commands can be executed
+while the original command remains suspended.  The suspended command can
+be continued using the
+.I fg
+command with no arguments.  The shell will then retype the command
+to remind you which command is being continued, and cause the command
+to resume execution.  Unless any input files in use by the suspended
+command have been changed in the meantime, the suspension has no effect
+whatsoever on the execution of the command.  This feature can be very useful
+during editing, when you need to look at another file before continuing.
+An
+example of command suspension follows.
+.DS
+% mail harold
+Someone just copied a big file into my directory and its name is
+^Z
+Stopped
+% ls
+funnyfile
+prog.c
+prog.o
+% jobs
+.ta 1.75i
+[1]  + Stopped	mail harold
+% fg
+mail harold
+funnyfile. Do you know who did it?
+EOT
+%
+.so tabs
+.DE
+In this example someone was sending a message to Harold and forgot the
+name of the file he wanted to mention.  The mail command was suspended
+by typing ^Z.  When the shell noticed that the mail program was
+suspended, it typed `Stopped' and prompted for a new command.  Then the
+.I ls
+command was typed to find out the name of the file.  The
+.I jobs
+command was run to find out which command was suspended.
+At this time the
+.I fg
+command was typed to continue execution of the mail program.  Input
+to the mail program was then continued and ended with a ^D
+which indicated the end of the message at which time the mail
+program typed EOT.  The
+.I jobs
+command will show which commands are suspended.
+The ^Z should only be typed at the beginning of a line since
+everything typed on the current line is discarded when a signal is sent
+from the keyboard.  This also happens on \s-2INTERRUPT\s0, and \s-2QUIT\s0
+signals.  More information on
+suspending jobs and controlling them is given in
+section 2.6.
+.PP
+If you write or run programs which are not fully debugged then it may
+be necessary to stop them somewhat ungracefully.
+This can be done by sending them a \s-2QUIT\s0
+signal, sent by typing a ^\e.
+This will usually provoke the shell to produce a message like:
+.DS
+Quit (Core dumped)
+.DE
+indicating that a file
+`core' has been created containing information about the running program's
+state when it terminated due to the \s-2QUIT\s0 signal.
+You can examine this file yourself, or forward information to the
+maintainer of the program telling him/her where the
+.I "core file"
+is.
+.PP
+If you run background commands (as explained in section 2.6) then these
+commands will ignore \s-2INTERRUPT\s0 and \s-2QUIT\s0 signals at the
+terminal.  To stop them you must use the
+.I kill
+command.  See section 2.6 for an example.
+.PP
+If you want to examine the output of a command without having it move
+off the screen as the output of the
+.DS
+cat /etc/passwd
+.DE
+command will, you can use the command
+.DS
+more /etc/passwd
+.DE
+The
+.I more
+program pauses after each complete screenful and types `\-\-More\-\-'
+at which point you can hit a space to get another screenful, a return
+to get another line, a `?' to get some help on other commands, or a `q' to end the
+.I more
+program.  You can also use more as a filter, i.e.
+.DS
+cat /etc/passwd | more
+.DE
+works just like the more simple more command above.
+.PP
+For stopping output of commands not involving
+.I more
+you can use the
+^S key to stop the typeout.  The typeout will resume when you
+hit ^Q or any other key, but ^Q is normally used because
+it only restarts the output and does not become input to the program
+which is running.  This works well on low-speed terminals, but at 9600
+baud it is hard to type ^S and ^Q fast enough to paginate
+the output nicely, and a program like
+.I more
+is usually used.
+.PP
+An additional possibility is to use the ^O flush output
+character; when this character is typed, all output from the current
+command is thrown away (quickly) until the next input read occurs
+or until the next shell prompt.  This can be used to allow a command
+to complete without having to suffer through the output on a slow
+terminal; ^O is a toggle, so flushing can be turned off by
+typing ^O again while output is being flushed.
+.NH 2
+What now?
+.PP
+We have so far seen a number of mechanisms of the shell and learned a lot
+about the way in which it operates.
+The remaining sections will go yet further into the internals of the
+shell, but you will surely want to try using the
+shell before you go any further.
+To try it you can log in to \s-2UNIX\s0 and type the following
+command to the system:
+.DS
+chsh myname /bin/csh
+.DE
+Here `myname' should be replaced by the name you typed to
+the system prompt of `login:' to get onto the system.
+Thus I would use `chsh bill /bin/csh'.
+.B
+You only have to do this once; it takes effect at next login.
+.R
+You are now ready to try using
+.I csh.
+.PP
+Before you do the `chsh' command, the shell you are using when
+you log into the system is `/bin/sh'.
+In fact, much of the above discussion is applicable to `/bin/sh'.
+The next section will introduce many features particular to
+.I csh
+so you should change your shell to
+.I csh
+before you begin reading it.
+.bp
diff --git a/share/doc/usd/04.csh/csh.2 b/share/doc/usd/04.csh/csh.2
new file mode 100644
index 0000000..5fbf43c
--- /dev/null
+++ b/share/doc/usd/04.csh/csh.2
@@ -0,0 +1,1304 @@
+.\"-
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)csh.2	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.nr H1 1
+.NH
+Details on the shell for terminal users
+.NH 2
+Shell startup and termination
+.PP
+When you login, the shell is started by the system in your
+.I home
+directory and begins by reading commands from a file
+.I \&.cshrc
+in this directory.
+All shells which you may start during your terminal session will
+read from this file.
+We will later see what kinds of commands are usefully placed there.
+For now we need not have this file and the shell does not complain about
+its absence.
+.PP
+A
+.I "login shell" ,
+executed after you login to the system,
+will, after it reads commands from
+.I \&.cshrc,
+read commands from a file
+.I \&.login
+also in your home directory.
+This file contains commands which you wish to do each time you login
+to the \s-2UNIX\s0 system.
+My
+.I \&.login
+file looks something like:
+.DS
+set ignoreeof
+set mail=(/usr/spool/mail/bill)
+echo "${prompt}users" ; users
+alias ts \e
+	\'set noglob ; eval \`tset \-s \-m dialup:c100rv4pna \-m plugboard:?hp2621nl \!*\`\';
+ts; stty intr ^C kill ^U crt
+set time=15 history=10
+msgs \-f
+if (\-e $mail) then
+	echo "${prompt}mail"
+	mail
+endif
+.DE
+.PP
+This file contains several commands to be executed by \s-2UNIX\s0
+each time I login.
+The first is a
+.I set
+command which is interpreted directly by the shell.  It sets the shell
+variable
+.I ignoreeof
+which causes the shell to not log me off if I hit ^D.  Rather,
+I use the
+.I logout
+command to log off of the system.
+By setting the
+.I mail
+variable, I ask the shell to watch for incoming mail to me.  Every 5 minutes
+the shell looks for this file and tells me if more mail has arrived there.
+An alternative to this is to put the command
+.DS
+biff y
+.DE
+in place of this
+.I set;
+this will cause me to be notified immediately when mail arrives, and to
+be shown the first few lines of the new message.
+.PP
+Next I set the shell variable `time' to `15' causing the shell to automatically
+print out statistics lines for commands which execute for at least 15 seconds
+of \s-2CPU\s+2 time.  The variable `history' is set to 10 indicating that
+I want the shell to remember the last 10 commands I type in its
+.I "history list" ,
+(described later).
+.PP
+I create an
+.I alias
+``ts'' which executes a
+\fItset\fR\|(1) command setting up the modes of the terminal.
+The parameters to
+.I tset
+indicate the kinds of terminal which I usually use when not on a hardwired
+port.  I then execute ``ts'' and also use the
+.I stty
+command to change the interrupt character to ^C and the line kill
+character to ^U.
+.PP
+I then run the `msgs' program, which provides me with any
+system messages which I have not seen before; the `\-f' option here prevents
+it from telling me anything if there are no new messages.
+Finally, if my mailbox file exists, then I run the `mail' program to
+process my mail.
+.PP
+When the `mail' and `msgs' programs finish, the shell will finish
+processing my
+.I \&.login
+file and begin reading commands from the terminal, prompting for each with
+`% '.
+When I log off (by giving the
+.I logout
+command) the shell
+will print `logout' and execute commands from the file `.logout'
+if it exists in my home directory.
+After that the shell will terminate and \s-2UNIX\s0 will log
+me off the system.
+If the system is not going down, I will receive a new login message.
+In any case, after the `logout' message the shell is committed to terminating
+and will take no further input from my terminal.
+.NH 2
+Shell variables
+.PP
+The shell maintains a set of
+.I variables.
+We saw above the variables
+.I history
+and
+.I time
+which had values `10' and `15'.
+In fact, each shell variable has as value an array of
+zero or more
+.I strings.
+Shell variables may be assigned values by the set command.  It has
+several forms, the most useful of which was given above and is
+.DS
+set name=value
+.DE
+.PP
+Shell variables may be used to store values which are to
+be used in commands later through a substitution mechanism.
+The shell variables most commonly referenced are, however, those which the
+shell itself refers to.
+By changing the values of these variables one can directly affect the
+behavior of the shell.
+.PP
+One of the most important variables is the variable
+.I path.
+This variable contains a sequence of directory names where the shell
+searches for commands.
+The
+.I set
+command with no arguments
+shows the value of all variables currently defined (we usually say
+.I set)
+in the shell.
+The default value for path will be shown by
+.I set
+to be
+.DS
+% set
+.ta .75i
+argv	()
+cwd	/usr/bill
+home	/usr/bill
+path	(. /usr/ucb /bin /usr/bin)
+prompt	%
+shell	/bin/csh
+status	0
+term	c100rv4pna
+user	bill
+%
+.so tabs
+.DE
+This output indicates that the variable path points to the current
+directory `.' and then `/usr/ucb', `/bin' and `/usr/bin'.
+Commands which you may write might be in `.' (usually one of
+your directories).
+Commands developed at Berkeley, live in `/usr/ucb'
+while commands developed at Bell Laboratories live in `/bin' and `/usr/bin'.
+.PP
+A number of locally developed programs on the system live in the directory
+`/usr/local'.
+If we wish that all shells which we invoke to have
+access to these new programs we can place the command
+.DS
+set path=(. /usr/ucb /bin /usr/bin /usr/local)
+.DE
+in our file
+.I \&.cshrc
+in our home directory.
+Try doing this and then logging out and back in and do
+.DS
+set
+.DE
+again to see that the value assigned to
+.I path
+has changed.
+.FS \(dg
+Another directory that might interest you is /usr/new, which contains
+many useful user-contributed programs provided with Berkeley Unix.
+.FE
+.PP
+One thing you should be aware of is that the shell examines each directory
+which you insert into your path and determines which commands are contained
+there.  Except for the current directory `.', which the shell treats specially,
+this means that if commands are added to a directory in your search path after
+you have started the shell, they will not necessarily be found by the shell.
+If you wish to use a command which has been added in this way, you should
+give the command
+.DS
+rehash
+.DE
+to the shell, which will cause it to recompute its internal table of command
+locations, so that it will find the newly added command.
+Since the shell has to look in the current directory `.' on each command,
+placing it at the end of the path specification usually works equivalently
+and reduces overhead.
+.PP
+Other useful built in variables are the variable
+.I home
+which shows your home directory,
+.I cwd
+which contains your current working directory,
+the variable
+.I ignoreeof
+which can be set in your
+.I \&.login
+file to tell the shell not to exit when it receives an end-of-file from
+a terminal (as described above).
+The variable `ignoreeof'
+is one of several variables which the shell does not care about the
+value of, only whether they are
+.I set
+or
+.I unset.
+Thus to set this variable you simply do
+.DS
+set ignoreeof
+.DE
+and to unset it do
+.DS
+unset ignoreeof
+.DE
+These give the variable `ignoreeof' no value, but none is desired or required.
+.PP
+Finally, some other built-in shell variables of use are the
+variables
+.I noclobber
+and
+.I mail.
+The metasyntax
+.DS
+> filename
+.DE
+which redirects the standard output of a command
+will overwrite and destroy the previous contents of the named file.
+In this way you may accidentally overwrite a file which is valuable.
+If you would prefer that the shell not overwrite files in this
+way you can
+.DS
+set noclobber
+.DE
+in your
+.I \&.login
+file.
+Then trying to do
+.DS
+date > now
+.DE
+would cause a diagnostic if `now' existed already.
+You could type
+.DS
+date >!  now
+.DE
+if you really wanted to overwrite the contents of `now'.
+The `>!' is a special metasyntax indicating that clobbering the
+file is ok.\(dg
+.FS
+\(dgThe space between the `!' and the word `now' is critical here, as `!now'
+would be an invocation of the
+.I history
+mechanism, and have a totally different effect.
+.FE
+.NH 2
+The shell's history list
+.PP
+The shell can maintain a
+.I "history list"
+into which it places the words
+of previous commands.
+It is possible to use a notation to reuse commands or words
+from commands in forming new commands.
+This mechanism can be used to repeat previous commands or to
+correct minor typing mistakes in commands.
+.PP
+The following figure gives a sample session involving typical usage of the
+history mechanism of the shell.
+.KF
+.DS
+% cat bug.c
+main()
+
+{
+	printf("hello);
+}
+% cc !$
+cc bug.c
+"bug.c", line 4: newline in string or char constant
+"bug.c", line 5: syntax error
+% ed !$
+ed bug.c
+29
+4s/);/"&/p
+        printf("hello");
+w
+30
+q
+% !c
+cc bug.c
+% a.out
+hello% !e
+ed bug.c
+30
+4s/lo/lo\e\en/p
+        printf("hello\en");
+w
+32
+q
+% !c \-o bug
+cc bug.c \-o bug
+% size a.out bug
+a.out: 2784+364+1028 = 4176b = 0x1050b
+bug: 2784+364+1028 = 4176b = 0x1050b
+% ls \-l !*
+ls \-l a.out bug
+\(mirwxr\(mixr\(mix 1 bill       3932 Dec 19 09:41 a.out
+\(mirwxr\(mixr\(mix 1 bill       3932 Dec 19 09:42 bug
+% bug
+hello
+% num bug.c | spp
+spp: Command not found.
+% ^spp^ssp
+num bug.c | ssp
+    1	main()
+    3	{
+    4		printf("hello\en");
+    5	}
+% !! | lpr
+num bug.c | ssp | lpr
+%
+.DE
+.KE
+In this example we have a very simple C program which has a bug (or two)
+in it in the file `bug.c', which we `cat' out on our terminal.  We then
+try to run the C compiler on it, referring to the file again as `!$',
+meaning the last argument to the previous command.  Here the `!' is the
+history mechanism invocation metacharacter, and the `$' stands for the last
+argument, by analogy to `$' in the editor which stands for the end of the line.
+The shell echoed the command, as it would have been typed without use of
+the history mechanism, and then executed it.
+The compilation yielded error diagnostics so we now run the editor on the
+file we were trying to compile, fix the bug, and run the C compiler again,
+this time referring to this command simply as `!c', which repeats the last
+command which started with the letter `c'.  If there were other
+commands starting with `c' done recently we could have said `!cc' or even
+`!cc:p' which would have printed the last command starting with `cc'
+without executing it.
+.PP
+After this recompilation, we ran the resulting `a.out' file, and then
+noting that there still was a bug, ran the editor again.  After fixing
+the program we ran the C compiler again, but tacked onto the command
+an extra `\-o bug' telling the compiler to place the resultant binary in
+the file `bug' rather than `a.out'.  In general, the history mechanisms
+may be used anywhere in the formation of new commands and other characters
+may be placed before and after the substituted commands.
+.PP
+We then ran the `size' command to see how large the binary program images
+we have created were, and then an `ls \-l' command with the same argument
+list, denoting the argument list `\!*'.
+Finally we ran the program `bug' to see that its output is indeed correct.
+.PP
+To make a numbered listing of the program we ran the `num' command on the file `bug.c'.
+In order to compress out blank lines in the output of `num' we ran the
+output through the filter `ssp', but misspelled it as spp.  To correct this
+we used a shell substitute, placing the old text and new text between `^'
+characters.  This is similar to the substitute command in the editor.
+Finally, we repeated the same command with `!!', but sent its output to the
+line printer.
+.PP
+There are other mechanisms available for repeating commands.  The
+.I history
+command prints out a number of previous commands with numbers by which
+they can be referenced.  There is a way to refer to a previous command
+by searching for a string which appeared in it, and there are other,
+less useful, ways to select arguments to include in a new command.
+A complete description of all these mechanisms
+is given in the C shell manual pages in the \s-2UNIX\s0 Programmer's Manual.
+.NH 2
+Aliases
+.PP
+The shell has an
+.I alias
+mechanism which can be used to make transformations on input commands.
+This mechanism can be used to simplify the commands you type,
+to supply default arguments to commands,
+or to perform transformations on commands and their arguments.
+The alias facility is similar to a macro facility.
+Some of the features obtained by aliasing can be obtained also
+using shell command files, but these take place in another instance
+of the shell and cannot directly affect the current shells environment
+or involve commands such as
+.I cd
+which must be done in the current shell.
+.PP
+As an example, suppose that there is a new version of the mail program
+on the system called `newmail'
+you wish to use, rather than the standard mail program which is called
+`mail'.
+If you place the shell command
+.DS
+alias mail newmail
+.DE
+in your
+.I \&.cshrc
+file, the shell will transform an input line of the form
+.DS
+mail bill
+.DE
+into a call on `newmail'.
+More generally, suppose we wish the command `ls' to always show
+sizes of files, that is to always do `\-s'.
+We can do
+.DS
+alias ls ls \-s
+.DE
+or even
+.DS
+alias dir ls \-s
+.DE
+creating a new command syntax `dir'
+which does an `ls \-s'.
+If we say
+.DS
+dir ~bill
+.DE
+then the shell will translate this to
+.DS
+ls \-s /mnt/bill
+.DE
+.PP
+Thus the
+.I alias
+mechanism can be used to provide short names for commands,
+to provide default arguments,
+and to define new short commands in terms of other commands.
+It is also possible to define aliases which contain multiple
+commands or pipelines, showing where the arguments to the original
+command are to be substituted using the facilities of the
+history mechanism.
+Thus the definition
+.DS
+alias cd \'cd \e!* ; ls \'
+.DE
+would do an
+.I ls
+command after each change directory
+.I cd
+command.
+We enclosed the entire alias definition in `\'' characters to prevent
+most substitutions from occurring and the character `;' from being
+recognized as a metacharacter.
+The `!' here is escaped with a `\e' to prevent it from being interpreted
+when the alias command is typed in.
+The `\e!*' here substitutes the entire argument list to the pre-aliasing
+.I cd
+command, without giving an error if there were no arguments.
+The `;' separating commands is used here
+to indicate that one command is to be done and then the next.
+Similarly the definition
+.DS
+alias whois \'grep \e!^ /etc/passwd\'
+.DE
+defines a command which looks up its first argument in the password file.
+.PP
+.B Warning:
+The shell currently reads the
+.I \&.cshrc
+file each time it starts up.  If you place a large number of commands
+there, shells will tend to start slowly.  A mechanism for saving the shell
+environment after reading the \fI\&.cshrc\fR file and quickly restoring it is
+under development, but for now you should try to limit the number of
+aliases you have to a reasonable number... 10 or 15 is reasonable,
+50 or 60 will cause a noticeable delay in starting up shells, and make
+the system seem sluggish when you execute commands from within the editor
+and other programs.
+.NH 2
+More redirection; >> and >&
+.PP
+There are a few more notations useful to the terminal user
+which have not been introduced yet.
+.PP
+In addition to the standard output, commands also have a
+.I "diagnostic output"
+which is normally directed to the terminal even when the standard output
+is redirected to a file or a pipe.
+It is occasionally desirable to direct the diagnostic output along with
+the standard output.
+For instance if you want to redirect the output of a long running command
+into a file and wish to have a record of any error diagnostic it produces
+you can do
+.DS
+command >& file
+.DE
+The `>&' here tells the shell to route both the diagnostic output and the
+standard output into `file'.
+Similarly you can give the command
+.DS
+command |\|& lpr
+.DE
+to route both standard and diagnostic output through the pipe
+to the line printer daemon
+.I lpr.\(dd
+.FS
+\(dd A command of the form
+.br
+.ti +5
+command >&! file
+.br
+exists, and is used when
+.I noclobber
+is set and
+.I file
+already exists.
+.FE
+.PP
+Finally, it is possible to use the form
+.DS
+command >> file
+.DE
+to place output at the end of an existing file.\(dg
+.FS
+\(dg If
+.I noclobber
+is set, then an error will result if
+.I file
+does not exist, otherwise the shell will create
+.I file
+if it doesn't exist.
+A form
+.br
+.ti +5
+command >>! file
+.br
+makes it not be an error for file to not exist when
+.I noclobber
+is set.
+.FE
+.NH 2
+Jobs; Background, Foreground, or Suspended
+.PP
+When one or more commands
+are typed together as a pipeline or as a sequence of commands separated by
+semicolons, a single
+.I job
+is created by the shell consisting of these commands together as a unit.
+Single commands without pipes or semicolons create the simplest jobs.
+Usually, every line typed to the shell creates a job.
+Some lines that create jobs (one per line) are
+.DS
+sort < data
+ls \-s | sort \-n | head \-5
+mail harold
+.DE
+.PP
+If the metacharacter `&' is typed
+at the end of the commands, then the job is started as a
+.I background
+job.  This means that the shell does not wait for it to complete but
+immediately prompts and is ready for another command.  The job runs
+.I "in the background"
+at the same time that normal jobs, called
+.I foreground
+jobs, continue to be read and executed by the shell one at a time.
+Thus
+.DS
+du > usage &
+.DE
+would run the
+.I du
+program, which reports on the disk usage of your working directory (as well as
+any directories below it), put the output into the file `usage' and return
+immediately with a prompt for the next command without out waiting for
+.I du
+to finish.  The
+.I du
+program would continue executing in the background
+until it finished, even though you can type and execute more commands in the
+mean time.
+When a background
+job terminates, a message is typed by the shell just before the next prompt
+telling you that the job has completed.
+In the following example the
+.I du
+job finishes sometime during the
+execution of the
+.I mail
+command and its completion is reported just before
+the prompt after the
+.I mail
+job is finished.
+.DS
+% du > usage &
+[1] 503
+% mail bill
+How do you know when a background job is finished?
+EOT
+.ta 1.75i
+[1] \- Done	du > usage
+%
+.so tabs
+.DE
+If the job did not terminate normally the `Done' message might say
+something else like `Killed'.
+If you want the
+terminations of background jobs to be reported at the time they occur
+(possibly interrupting the output of other foreground jobs), you can set
+the
+.I notify
+variable.  In the previous example this would mean that the
+`Done' message might have come right in the middle of the message to
+Bill.
+Background jobs are unaffected by any signals from the keyboard like
+the \s-2STOP\s0, \s-2INTERRUPT\s0, or \s-2QUIT\s0 signals mentioned earlier.
+.PP
+Jobs are recorded in a table inside the shell until they terminate.
+In this table, the shell remembers the command names, arguments and the
+.I "process numbers"
+of all commands in the job as well as the working directory where the job was
+started.
+Each job in the table is either running
+.I "in the foreground"
+with the shell waiting for it to terminate, running
+.I "in the background,"
+or
+.I suspended.
+Only one job can be running in the foreground at one time, but several
+jobs can be suspended or running in the background at once.  As each job
+is started, it is assigned a small identifying
+number called the
+.I "job number"
+which can be used later to refer to the job in the commands described below.
+Job numbers remain
+the same until the job terminates and then are re-used.
+.PP
+When a job is started in the background using `&', its number, as well
+as the process numbers of all its (top level) commands, is typed by the shell
+before prompting you for another command.
+For example,
+.DS
+% ls \-s | sort \-n > usage &
+[2] 2034 2035
+%
+.DE
+runs the `ls' program with the `\-s' options, pipes this output into
+the `sort' program with the `\-n' option which puts its output into the
+file `usage'.
+Since the `&' was at the end of the line, these two programs were started
+together as a background job.  After starting the job, the shell prints
+the job number in brackets (2 in this case) followed by the process number
+of each program started in the job.  Then the shell immediates prompts for
+a new command, leaving the job running simultaneously.
+.PP
+As mentioned in section 1.8, foreground jobs become
+.I suspended
+by typing ^Z
+which sends a \s-2STOP\s0 signal to the currently running
+foreground job.  A background job can become suspended by using the
+.I stop
+command described below.  When jobs are suspended they merely stop
+any further progress until started again, either in the foreground
+or the background.  The shell notices when a job becomes stopped and
+reports this fact, much like it reports the termination of background jobs.
+For foreground jobs this looks like
+.DS
+% du > usage
+^Z
+Stopped
+%
+.DE
+`Stopped' message is typed by the shell when it notices that the
+.I du
+program stopped.
+For background jobs, using the
+.I stop
+command, it is
+.DS
+% sort usage &
+[1] 2345
+% stop %1
+.ta 1.75i
+[1] + Stopped (signal)	sort usage
+%
+.so tabs
+.DE
+Suspending foreground jobs can be very useful when you need to temporarily
+change what you are doing (execute other commands) and then return to
+the suspended job.  Also, foreground jobs can be suspended and then
+continued as background jobs using the
+.I bg
+command, allowing you to continue other work and
+stop waiting for the foreground job to finish.  Thus
+.DS
+% du > usage
+^Z
+Stopped
+% bg
+[1] du > usage &
+%
+.DE
+starts `du' in the foreground, stops it before it finishes, then continues
+it in the background allowing more foreground commands to be executed.
+This is especially helpful
+when a foreground job ends up taking longer than you expected and you
+wish you had started it in the background in the beginning.
+.PP
+All
+.I "job control"
+commands can take an argument that identifies a particular
+job.
+All job name arguments begin with the character `%', since some of the
+job control commands also accept process numbers (printed by the
+.I ps
+command.)
+The default job (when no argument is given) is called the
+.I current
+job and is identified by a `+' in the output of the
+.I jobs
+command, which shows you which jobs you have.
+When only one job is stopped or running in the background (the usual case)
+it is always the current job thus no argument is needed.
+If a job is stopped while running in the foreground it becomes the
+.I current
+job and the existing current job becomes the
+.I previous
+job \- identified by a `\-' in the output of
+.I jobs.
+When the current job terminates, the previous job becomes the current job.
+When given, the argument is either `%\-' (indicating
+the previous job); `%#', where # is the job number;
+`%pref' where pref is some unique prefix of the command name
+and arguments of one of the jobs; or `%?' followed by some string found
+in only one of the jobs.
+.PP
+The
+.I jobs
+command types the table of jobs, giving the job number,
+commands and status (`Stopped' or `Running') of each background or
+suspended job.  With the `\-l' option the process numbers are also
+typed.
+.DS
+% du > usage &
+[1] 3398
+% ls \-s | sort \-n > myfile &
+[2] 3405
+% mail bill
+^Z
+Stopped
+% jobs
+.ta 1.75i
+[1] \(mi Running	du > usage
+[2]    Running	ls \-s | sort \-n > myfile
+[3] \(pl Stopped	mail bill
+% fg %ls
+ls \-s | sort \-n > myfile
+% more myfile
+.so tabs
+.DE
+.PP
+The
+.I fg
+command runs a suspended or background job in the foreground.  It is
+used to restart a previously suspended job or change a background job
+to run in the foreground (allowing signals or input from the terminal).
+In the above example we used
+.I fg
+to change the `ls' job from the
+background to the foreground since we wanted to wait for it to
+finish before looking at its output file.
+The
+.I bg
+command runs a suspended job in the background.  It is usually used
+after stopping the currently running foreground job with the
+\s-2STOP\s0 signal.  The combination of the \s-2STOP\s0 signal and the
+.I bg
+command changes a foreground job into a background job.
+The
+.I stop
+command suspends a background job.
+.PP
+The
+.I kill
+command terminates a background or suspended job immediately.
+In addition to jobs, it may be given process numbers as arguments,
+as printed by
+.I ps.
+Thus, in the example above, the running
+.I du
+command could have been terminated by the command
+.DS
+% kill %1
+.ta 1.75i
+[1]  Terminated	du > usage
+%
+.so tabs
+.DE
+.PP
+The
+.I notify
+command (not the variable mentioned earlier) indicates that the termination
+of a specific job should be
+reported at the time it finishes instead of waiting for the next prompt.
+.PP
+If a job running in the background tries to read input from the terminal
+it is automatically stopped.  When such a job is then run in the
+foreground, input can be given to the job.  If desired, the job can
+be run in the background again until it requests input again.
+This is illustrated in the following sequence where the `s' command in the
+text editor might take a long time.
+.ID
+.nf
+% ed bigfile
+120000
+1,$s/thisword/thatword/
+^Z
+Stopped
+% bg
+[1] ed bigfile &
+%
+ . . .  some foreground commands
+.ta 1.75i
+[1] Stopped (tty input)	ed bigfile
+% fg
+ed bigfile
+w
+120000
+q
+%
+.so tabs
+.DE
+So after the `s' command was issued, the `ed' job was stopped with ^Z
+and then put in the background using
+.I bg.
+Some time later when the `s' command was finished,
+.I ed
+tried to read another command and was stopped because jobs
+in the background cannot read from the terminal.  The
+.I fg
+command returned the `ed' job to the foreground where it could once again
+accept commands from the terminal.
+.PP
+The command
+.DS
+stty tostop
+.DE
+causes all background jobs run on your terminal to stop
+when they are about to
+write output to the terminal.  This prevents messages from background
+jobs from interrupting foreground job output and allows you to run
+a job in the background without losing terminal output.  It also
+can be used for interactive programs that sometimes have long
+periods without interaction.  Thus each time it outputs a prompt for more
+input it will stop before the prompt.  It can then be run in the
+foreground using
+.I fg,
+more input can be given and, if necessary stopped and returned to
+the background.  This
+.I stty
+command might be a good thing to put in your
+.I \&.login
+file if you do not like output from background jobs interrupting
+your work.  It also can reduce the need for redirecting the output
+of background jobs if the output is not very big:
+.DS
+% stty tostop
+% wc hugefile &
+[1] 10387
+% ed text
+\&. . . some time later
+q
+.ta 1.75i
+[1] Stopped (tty output)	wc hugefile
+% fg wc
+wc hugefile
+   13371   30123   302577
+% stty \-tostop
+.so tabs
+.DE
+Thus after some time the `wc' command, which counts the lines, words
+and characters in a file, had one line of output.  When it tried to
+write this to the terminal it stopped.  By restarting it in the
+foreground we allowed it to write on the terminal exactly when we were
+ready to look at its output.
+Programs which attempt to change the mode of the terminal will also
+block, whether or not
+.I tostop
+is set, when they are not in the foreground, as
+it would be very unpleasant to have a background job change the state
+of the terminal.
+.PP
+Since the
+.I jobs
+command only prints jobs started in the currently executing shell,
+it knows nothing about background jobs started in other login sessions
+or within shell files.  The
+.I ps
+can be used in this case to find out about background jobs not started
+in the current shell.
+.NH 2
+Working Directories
+.PP
+As mentioned in section 1.6, the shell is always in a particular
+.I "working directory."
+The `change directory' command
+.I chdir
+(its
+short form
+.I cd
+may also be used)
+changes the working directory of the shell,
+that is, changes the directory you
+are located in.
+.PP
+It is useful to make a directory for each project you wish to work on
+and to place all files related to that project in that directory.
+The `make directory' command,
+.I mkdir,
+creates a new directory.
+The
+.I pwd
+(`print working directory') command
+reports the absolute pathname of the working directory of the shell,
+that is, the directory you are
+located in.
+Thus in the example below:
+.DS
+% pwd
+/usr/bill
+% mkdir newpaper
+% chdir newpaper
+% pwd
+/usr/bill/newpaper
+%
+.DE
+the user has created and moved to the
+directory
+.I newpaper.
+where, for example, he might
+place a group of related files.
+.PP
+No matter where you have moved to in a directory hierarchy,
+you can return to your `home' login directory by doing just
+.DS
+cd
+.DE
+with no arguments.
+The name `..' always means the directory above the current one in
+the hierarchy, thus
+.DS
+cd ..
+.DE
+changes the shell's working directory to the one directly above the
+current one.
+The name `..' can be used in any
+pathname, thus,
+.DS
+cd ../programs
+.DE
+means
+change to the directory `programs' contained in the directory
+above the current one.
+If you have several directories for different
+projects under, say, your home directory,
+this shorthand notation
+permits you to switch easily between them.
+.PP
+The shell always remembers the pathname of its current working directory in
+the variable
+.I cwd.
+The shell can also be requested to remember the previous directory when
+you change to a new working directory.  If the `push directory' command
+.I pushd
+is used in place of the
+.I cd
+command, the shell saves the name of the current working directory
+on a
+.I "directory stack"
+before changing to the new one.
+You can see this list at any time by typing the `directories'
+command
+.I dirs.
+.ID
+.nf
+% pushd newpaper/references
+~/newpaper/references  ~
+% pushd /usr/lib/tmac
+/usr/lib/tmac  ~/newpaper/references  ~
+% dirs
+/usr/lib/tmac  ~/newpaper/references  ~
+% popd
+~/newpaper/references  ~
+% popd
+~
+%
+.DE
+The list is printed in a horizontal line, reading left to right,
+with a tilde (~) as
+shorthand for your home directory\(emin this case `/usr/bill'.
+The directory stack is printed whenever there is more than one
+entry on it and it changes.
+It is also printed by a
+.I dirs
+command.
+.I Dirs
+is usually faster and more informative than
+.I pwd
+since it shows the current working directory as well as any
+other directories remembered in the stack.
+.PP
+The
+.I pushd
+command with no argument
+alternates the current directory with the first directory in the
+list.
+The `pop directory'
+.I popd
+command without an argument returns you to the directory you were in prior to
+the current one, discarding the previous current directory from the
+stack (forgetting it).
+Typing
+.I popd
+several times in a series takes you backward through the directories
+you had been in (changed to) by
+.I pushd
+command.
+There are other options to
+.I pushd
+and
+.I popd
+to manipulate the contents of the directory stack and to change
+to directories not at the top of the stack; see the
+.I csh
+manual page for details.
+.PP
+Since the shell remembers the working directory in which each job
+was started, it warns you when you might be confused by restarting
+a job in the foreground which has a different working directory than the
+current working directory of the shell.  Thus if you start a background
+job, then change the shell's working directory and then cause the
+background job to run in the foreground, the shell warns you that the
+working directory of the currently running foreground job is different
+from that of the shell.
+.DS
+% dirs \-l
+/mnt/bill
+% cd myproject
+% dirs
+~/myproject
+% ed prog.c
+1143
+^Z
+Stopped
+% cd ..
+% ls
+myproject
+textfile
+% fg
+ed prog.c (wd: ~/myproject)
+.DE
+This way the shell warns you when there
+is an implied change of working directory, even though no cd command was
+issued.  In the above example the `ed' job was still in `/mnt/bill/project'
+even though the shell had changed to `/mnt/bill'.
+A similar warning is given when such a foreground job
+terminates or is suspended (using the \s-2STOP\s0 signal) since
+the return to the shell again implies a change of working directory.
+.DS
+% fg
+ed prog.c (wd: ~/myproject)
+ . . . after some editing
+q
+(wd now: ~)
+%
+.DE
+These messages are sometimes confusing if you use programs that change
+their own working directories, since the shell only remembers which
+directory a job is started in, and assumes it stays there.
+The `\-l' option of
+.I jobs
+will type the working directory
+of suspended or background jobs when it is different
+from the current working directory of the shell.
+.NH 2
+Useful built-in commands
+.PP
+We now give a few of the useful built-in commands of the shell describing
+how they are used.
+.PP
+The
+.I alias
+command described above is used to assign new aliases and to show the
+existing aliases.
+With no arguments it prints the current aliases.
+It may also be given only one argument such as
+.DS
+alias ls
+.DE
+to show the current alias for, e.g., `ls'.
+.PP
+The
+.I echo
+command prints its arguments.
+It is often used in
+.I "shell scripts"
+or as an interactive command
+to see what filename expansions will produce.
+.PP
+The
+.I history
+command will show the contents of the history list.
+The numbers given with the history events can be used to reference
+previous events which are difficult to reference using the
+contextual mechanisms introduced above.
+There is also a shell variable called
+.I prompt.
+By placing a `!' character in its value the shell will there substitute
+the number of the current command in the history list.
+You can use this number to refer to this command in a history substitution.
+Thus you could
+.DS
+set prompt=\'\e! % \'
+.DE
+Note that the `!' character had to be
+.I escaped
+here even within `\'' characters.
+.PP
+The
+.I limit
+command is used to restrict use of resources.
+With no arguments it prints the current limitations:
+.DS
+.ta 1i
+cputime	unlimited
+filesize	unlimited
+datasize	5616 kbytes
+stacksize	512 kbytes
+coredumpsize	unlimited
+.so tabs
+.DE
+Limits can be set, e.g.:
+.DS
+limit coredumpsize 128k
+.DE
+Most reasonable units abbreviations will work; see the
+.I csh
+manual page for more details.
+.PP
+The
+.I logout
+command can be used to terminate a login shell which has
+.I ignoreeof
+set.
+.PP
+The
+.I rehash
+command causes the shell to recompute a table of where commands are
+located.  This is necessary if you add a command to a directory
+in the current shell's search path and wish the shell to find it,
+since otherwise the hashing algorithm may tell the shell that the
+command wasn't in that directory when the hash table was computed.
+.PP
+The
+.I repeat
+command can be used to repeat a command several times.
+Thus to make 5 copies of the file
+.I one
+in the file
+.I five
+you could do
+.DS
+repeat 5 cat one >> five
+.DE
+.PP
+The
+.I setenv
+command can be used
+to set variables in the environment.
+Thus
+.DS
+setenv TERM adm3a
+.DE
+will set the value of the environment variable \s-2TERM\s0
+to
+`adm3a'.
+A user program
+.I printenv
+exists which will print out the environment.
+It might then show:
+.DS
+% printenv
+HOME=/usr/bill
+SHELL=/bin/csh
+PATH=:/usr/ucb:/bin:/usr/bin:/usr/local
+TERM=adm3a
+USER=bill
+%
+.DE
+.PP
+The
+.I source
+command can be used to force the current shell to read commands from
+a file.
+Thus
+.DS
+source .cshrc
+.DE
+can be used after editing in a change to the
+.I \&.cshrc
+file which you wish to take effect right away.
+.PP
+The
+.I time
+command can be used to cause a command to be timed no matter how much
+\s-2CPU\s0 time it takes.
+Thus
+.DS
+% time cp /etc/rc /usr/bill/rc
+0.0u 0.1s 0:01 8% 2+1k 3+2io 1pf+0w
+% time wc /etc/rc /usr/bill/rc
+     52    178   1347 /etc/rc
+     52    178   1347 /usr/bill/rc
+    104    356   2694 total
+0.1u 0.1s 0:00 13% 3+3k 5+3io 7pf+0w
+%
+.DE
+indicates that the
+.I cp
+command used a negligible amount of user time (u)
+and about 1/10th of a system time (s); the elapsed time was 1 second (0:01),
+there was an average memory usage of 2k bytes of program space and 1k
+bytes of data space over the cpu time involved (2+1k); the program
+did three disk reads and two disk writes (3+2io), and took one page fault
+and was not swapped (1pf+0w).
+The word count command
+.I wc
+on the other hand used 0.1 seconds of user time and 0.1 seconds of system
+time in less than a second of elapsed time.
+The percentage `13%' indicates that over the period when it was active
+the command `wc' used an average of 13 percent of the available \s-2CPU\s0
+cycles of the machine.
+.PP
+The
+.I unalias
+and
+.I unset
+commands can be used
+to remove aliases and variable definitions from the shell, and
+.I unsetenv
+removes variables from the environment.
+.NH 2
+What else?
+.PP
+This concludes the basic discussion of the shell for terminal users.
+There are more features of the shell to be discussed here, and all
+features of the shell are discussed in its manual pages.
+One useful feature which is discussed later is the
+.I foreach
+built-in command which can be used to run the same command
+sequence with a number of different arguments.
+.PP
+If you intend to use \s-2UNIX\s0 a lot you should look through
+the rest of this document and the csh manual pages (section1) to become familiar
+with the other facilities which are available to you.
+.bp
diff --git a/share/doc/usd/04.csh/csh.3 b/share/doc/usd/04.csh/csh.3
new file mode 100644
index 0000000..76ee1eb
--- /dev/null
+++ b/share/doc/usd/04.csh/csh.3
@@ -0,0 +1,649 @@
+.\"-
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)csh.3	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.nr H1 2
+.NH
+Shell control structures and command scripts
+.NH 2
+Introduction
+.PP
+It is possible to place commands in files and to cause shells to be
+invoked to read and execute commands from these files,
+which are called
+.I "shell scripts."
+We here detail those features of the shell useful to the writers of such
+scripts.
+.NH 2
+Make
+.PP
+It is important to first note what shell scripts are
+.I not
+useful for.
+There is a program called
+.I make
+which is very useful for maintaining a group of related files
+or performing sets of operations on related files.
+For instance a large program consisting of one or more files
+can have its dependencies described in a
+.I makefile
+which contains definitions of the commands used to create these
+different files when changes occur.
+Definitions of the means for printing listings, cleaning up the directory
+in which the files reside, and installing the resultant programs
+are easily, and most appropriately placed in this
+.I makefile.
+This format is superior and preferable to maintaining a group of shell
+procedures to maintain these files.
+.PP
+Similarly when working on a document a
+.I makefile
+may be created which defines how different versions of the document
+are to be created and which options of
+.I nroff
+or
+.I troff
+are appropriate.
+.NH 2
+Invocation and the argv variable
+.PP
+A
+.I csh
+command script may be interpreted by saying
+.DS
+% csh script ...
+.DE
+where
+.I script
+is the name of the file containing a group of
+.I csh
+commands and
+`\&...' is replaced by a sequence of arguments.
+The shell places these arguments in the variable
+.I argv
+and then begins to read commands from the script.
+These parameters are then available through the same mechanisms
+which are used to reference any other shell variables.
+.PP
+If you make the file
+`script'
+executable by doing
+.DS
+chmod 755 script
+.DE
+and place a shell comment at the beginning of the shell script
+(i.e. begin the file with a `#' character)
+then a `/bin/csh' will automatically be invoked to execute `script' when
+you type
+.DS
+script
+.DE
+If the file does not begin with a `#' then the standard shell
+`/bin/sh' will be used to execute it.
+This allows you to convert your older shell scripts to use
+.I csh
+at your convenience.
+.NH 2
+Variable substitution
+.PP
+After each input line is broken into words and history substitutions
+are done on it, the input line is parsed into distinct commands.
+Before each command is executed a mechanism know as
+.I "variable substitution"
+is done on these words.
+Keyed by the character `$' this substitution replaces the names
+of variables by their values.
+Thus
+.DS
+echo $argv
+.DE
+when placed in a command script would cause the current value of the
+variable
+.I argv
+to be echoed to the output of the shell script.
+It is an error for
+.I argv
+to be unset at this point.
+.PP
+A number of notations are provided for accessing components and attributes
+of variables.
+The notation
+.DS
+$?name
+.DE
+expands to `1' if name is
+.I set
+or to `0'
+if name is not
+.I set.
+It is the fundamental mechanism used for checking whether particular
+variables have been assigned values.
+All other forms of reference to undefined variables cause errors.
+.PP
+The notation
+.DS
+$#name
+.DE
+expands to the number of elements in the variable
+.I name.
+Thus
+.DS
+% set argv=(a b c)
+% echo $?argv
+1
+% echo $#argv
+3
+% unset argv
+% echo $?argv
+0
+% echo $argv
+Undefined variable: argv.
+%
+.DE
+.PP
+It is also possible to access the components of a variable
+which has several values.
+Thus
+.DS
+$argv[1]
+.DE
+gives the first component of
+.I argv
+or in the example above `a'.
+Similarly
+.DS
+$argv[$#argv]
+.DE
+would give `c',
+and
+.DS
+$argv[1\-2]
+.DE
+would give `a b'. Other notations useful in shell scripts are
+.DS
+$\fIn\fR
+.DE
+where
+.I n
+is an integer as a shorthand for
+.DS
+$argv[\fIn\fR\|]
+.DE
+the
+.I n\|th
+parameter and
+.DS
+$*
+.DE
+which is a shorthand for
+.DS
+$argv
+.DE
+The form
+.DS
+$$
+.DE
+expands to the process number of the current shell.
+Since this process number is unique in the system it can
+be used in generation of unique temporary file names.
+The form
+.DS
+$<
+.DE
+is quite special and is replaced by the next line of input read from
+the shell's standard input (not the script it is reading).  This is
+useful for writing shell scripts that are interactive, reading
+commands from the terminal, or even writing a shell script that
+acts as a filter, reading lines from its input file.
+Thus the sequence
+.DS
+echo 'yes or no?\ec'
+set a=($<)
+.DE
+would write out the prompt `yes or no?' without a newline and then
+read the answer into the variable `a'.  In this case `$#a' would be
+`0' if either a blank line or end-of-file (^D) was typed.
+.PP
+One minor difference between `$\fIn\fR\|' and `$argv[\fIn\fR\|]'
+should be noted here.
+The form
+`$argv[\fIn\fR\|]'
+will yield an error if
+.I n
+is not in the range
+`1\-$#argv'
+while `$n'
+will never yield an out of range subscript error.
+This is for compatibility with the way older shells handled parameters.
+.PP
+Another important point is that it is never an error to give a subrange
+of the form `n\-'; if there are less than
+.I n
+components of the given variable then no words are substituted.
+A range of the form `m\-n' likewise returns an empty vector without giving
+an error when \fIm\fR exceeds the number of elements of the given variable,
+provided the subscript \fIn\fR is in range.
+.NH 2
+Expressions
+.PP
+In order for interesting shell scripts to be constructed it
+must be possible to evaluate expressions in the shell based on the
+values of variables.
+In fact, all the arithmetic operations of the language C are available
+in the shell
+with the same precedence that they have in C.
+In particular, the operations `==' and `!=' compare strings
+and the operators `&&' and `|\|\||' implement the boolean and/or operations.
+The special operators `=~' and `!~' are similar to `==' and `!=' except
+that the string on the right side can have pattern matching characters
+(like *, ? or []) and the test is whether the string on the left matches
+the pattern on the right.
+.PP
+The shell also allows file enquiries of the form
+.DS
+\-? filename
+.DE
+where `?' is replace by a number of single characters.
+For instance the expression primitive
+.DS
+\-e filename
+.DE
+tell whether the file
+`filename'
+exists.
+Other primitives test for read, write and execute access to the file,
+whether it is a directory, or has non-zero length.
+.PP
+It is possible to test whether a command terminates normally,
+by a primitive of the
+form `{ command }' which returns true, i.e. `1' if the command
+succeeds exiting normally with exit status 0, or `0' if the command
+terminates abnormally or with exit status non-zero.
+If more detailed information about the execution status of a command
+is required, it can be executed and the variable `$status' examined
+in the next command.
+Since `$status' is set by every command, it is very transient.
+It can be saved if it is inconvenient to use it only in the single
+immediately following command.
+.PP
+For a full list of expression components available see the manual
+section for the shell.
+.NH 2
+Sample shell script
+.PP
+A sample shell script which makes use of the expression mechanism
+of the shell and some of its control structure follows:
+.DS
+% cat copyc
+#
+# Copyc copies those C programs in the specified list
+# to the directory ~/backup if they differ from the files
+# already in ~/backup
+#
+set noglob
+foreach i ($argv)
+
+        if ($i !~ *.c) continue  # not a .c file so do nothing
+
+        if (! \-r ~/backup/$i:t) then
+                echo $i:t not in backup... not cp\e\'ed
+                continue
+        endif
+
+        cmp \-s $i ~/backup/$i:t # to set $status
+
+        if ($status != 0) then
+                echo new backup of $i
+                cp $i ~/backup/$i:t
+        endif
+end
+.DE
+.PP
+This script makes use of the
+.I foreach
+command, which causes the shell to execute the commands between the
+.I foreach
+and the matching
+.I end
+for each of the values given between `(' and `)' with the named
+variable, in this case `i' set to successive values in the list.
+Within this loop we may use the command
+.I break
+to stop executing the loop
+and
+.I continue
+to prematurely terminate one iteration
+and begin the next.
+After the
+.I foreach
+loop the iteration variable
+(\fIi\fR in this case)
+has the value at the last iteration.
+.PP
+We set the variable
+.I noglob
+here to prevent filename expansion of the members of
+.I argv.
+This is a good idea, in general, if the arguments to a shell script
+are filenames which have already been expanded or if the arguments
+may contain filename expansion metacharacters.
+It is also possible to quote each use of a `$' variable expansion,
+but this is harder and less reliable.
+.PP
+The other control construct used here is a statement of the form
+.DS
+\fBif\fR ( expression ) \fBthen\fR
+	command
+	...
+\fBendif\fR
+.DE
+The placement of the keywords here is
+.B not
+flexible due to the current implementation of the shell.\(dg
+.FS
+\(dgThe following two formats are not currently acceptable to the shell:
+.sp
+.in +5
+.nf
+\fBif\fR ( expression )		# \fBWon't work!\fR
+\fBthen\fR
+	command
+	...
+\fBendif\fR
+.fi
+.in -5
+.sp
+and
+.sp
+.in +5
+.nf
+\fBif\fR ( expression ) \fBthen\fR command \fBendif\fR		# \fBWon't work\fR
+.in -5
+.fi
+.FE
+.PP
+The shell does have another form of the if statement of the form
+.DS
+\fBif\fR ( expression ) \fBcommand\fR
+.DE
+which can be written
+.DS
+\fBif\fR ( expression ) \e
+	command
+.DE
+Here we have escaped the newline for the sake of appearance.
+The command must not involve `\||\|', `&' or `;'
+and must not be another control command.
+The second form requires the final `\e' to
+.B immediately
+precede the end-of-line.
+.PP
+The more general
+.I if
+statements above also admit a sequence of
+.I else\-if
+pairs followed by a single
+.I else
+and an
+.I endif,
+e.g.:
+.DS
+\fBif\fR ( expression ) \fBthen\fR
+	commands
+\fBelse\fR \fBif\fR (expression ) \fBthen\fR
+	commands
+\&...
+
+\fBelse\fR
+	commands
+\fBendif\fR
+.DE
+.PP
+Another important mechanism used in shell scripts is the `:' modifier.
+We can use the modifier `:r' here to extract a root of a filename or
+`:e' to extract the
+.I extension.
+Thus if the variable
+.I i
+has the value
+`/mnt/foo.bar'
+then
+.sp
+.in +5
+.nf
+% echo $i $i:r $i:e
+/mnt/foo.bar /mnt/foo bar
+%
+.sp
+.in -5
+.fi
+shows how the `:r' modifier strips off the trailing `.bar' and the
+the `:e' modifier leaves only the `bar'.
+Other modifiers will take off the last component of a pathname leaving
+the head `:h' or all but the last component of a pathname leaving the
+tail `:t'.
+These modifiers are fully described in the
+.I csh
+manual pages in the User's Reference Manual.
+It is also possible to use the
+.I "command substitution"
+mechanism described in the next major section to perform modifications
+on strings to then reenter the shell's environment.
+Since each usage of this mechanism involves the creation of a new process,
+it is much more expensive to use than the `:' modification mechanism.\(dd
+.FS
+\(dd It is also important to note that
+the current implementation of the shell limits the number of `:' modifiers
+on a `$' substitution to 1.
+Thus
+.sp
+.nf
+.in +5
+% echo $i $i:h:t
+/a/b/c /a/b:t
+%
+.in -5
+.fi
+.sp
+does not do what one would expect.
+.FE
+Finally, we note that the character `#' lexically introduces a shell
+comment in shell scripts (but not from the terminal).
+All subsequent characters on the input line after a `#' are discarded
+by the shell.
+This character can be quoted using `\'' or `\e' to place it in
+an argument word.
+.NH 2
+Other control structures
+.PP
+The shell also has control structures
+.I while
+and
+.I switch
+similar to those of C.
+These take the forms
+.DS
+\fBwhile\fR ( expression )
+	commands
+\fBend\fR
+.DE
+and
+.DS
+\fBswitch\fR ( word )
+
+\fBcase\fR str1:
+	commands
+	\fBbreaksw\fR
+
+\& ...
+
+\fBcase\fR strn:
+	commands
+	\fBbreaksw\fR
+
+\fBdefault:\fR
+	commands
+	\fBbreaksw\fR
+
+\fBendsw\fR
+.DE
+For details see the manual section for
+.I csh.
+C programmers should note that we use
+.I breaksw
+to exit from a
+.I switch
+while
+.I break
+exits a
+.I while
+or
+.I foreach
+loop.
+A common mistake to make in
+.I csh
+scripts is to use
+.I break
+rather than
+.I breaksw
+in switches.
+.PP
+Finally,
+.I csh
+allows a
+.I goto
+statement, with labels looking like they do in C, i.e.:
+.DS
+loop:
+	commands
+	\fBgoto\fR loop
+.DE
+.NH 2
+Supplying input to commands
+.PP
+Commands run from shell scripts receive by default the standard
+input of the shell which is running the script.
+This is different from previous shells running
+under \s-2UNIX\s0.  It allows shell scripts to fully participate
+in pipelines, but mandates extra notation for commands which are to take
+inline data.
+.PP
+Thus we need a metanotation for supplying inline data to commands in
+shell scripts.
+As an example, consider this script which runs the editor to
+delete leading blanks from the lines in each argument file:
+.DS
+% cat deblank
+# deblank \-\- remove leading blanks
+foreach i ($argv)
+ed \- $i << \'EOF\'
+1,$s/^[ ]*//
+w
+q
+\&\'EOF\'
+end
+%
+.DE
+The notation `<< \'EOF\''
+means that the standard input for the
+.I ed
+command is to come from the text in the shell script file
+up to the next line consisting of exactly `\'EOF\''.
+The fact that the `EOF' is enclosed in `\'' characters, i.e. quoted,
+causes the shell to not perform variable substitution on the
+intervening lines.
+In general, if any part of the word following the `<<' which the
+shell uses to terminate the text to be given to the command is quoted
+then these substitutions will not be performed.
+In this case since we used the form `1,$' in our editor script
+we needed to insure that this `$' was not variable substituted.
+We could also have insured this by preceding the `$' here with a `\e',
+i.e.:
+.DS
+1,\e$s/^[ ]*//
+.DE
+but quoting the `EOF' terminator is a more reliable way of achieving the
+same thing.
+.NH 2
+Catching interrupts
+.PP
+If our shell script creates temporary files, we may wish to catch
+interruptions of the shell script so that we can clean up
+these files.
+We can then do
+.DS
+onintr label
+.DE
+where
+.I label
+is a label in our program.
+If an interrupt is received the shell will do a
+`goto label'
+and we can remove the temporary files and then do an
+.I exit
+command (which is built in to the shell)
+to exit from the shell script.
+If we wish to exit with a non-zero status we can do
+.DS
+exit(1)
+.DE
+e.g. to exit with status `1'.
+.NH 2
+What else?
+.PP
+There are other features of the shell useful to writers of shell
+procedures.
+The
+.I verbose
+and
+.I echo
+options and the related
+.I \-v
+and
+.I \-x
+command line options can be used to help trace the actions of the shell.
+The
+.I \-n
+option causes the shell only to read commands and not to execute
+them and may sometimes be of use.
+.PP
+One other thing to note is that
+.I csh
+will not execute shell scripts which do not begin with the
+character `#', that is shell scripts that do not begin with a comment.
+Similarly, the `/bin/sh' on your system may well defer to `csh'
+to interpret shell scripts which begin with `#'.
+This allows shell scripts for both shells to live in harmony.
+.PP
+There is also another quotation mechanism using `"' which allows
+only some of the expansion mechanisms we have so far discussed to occur
+on the quoted string and serves to make this string into a single word
+as `\'' does.
+.bp
diff --git a/share/doc/usd/04.csh/csh.4 b/share/doc/usd/04.csh/csh.4
new file mode 100644
index 0000000..7ef24dc
--- /dev/null
+++ b/share/doc/usd/04.csh/csh.4
@@ -0,0 +1,176 @@
+.\"-
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)csh.4	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.nr H1 3
+.NH
+Other, less commonly used, shell features
+.NH 2
+Loops at the terminal; variables as vectors
+.PP
+It is occasionally useful to use the
+.I foreach
+control structure at the terminal to aid in performing a number
+of similar commands.
+For instance, there were at one point three shells in use on the Cory \s-2UNIX\s0
+system at Cory Hall,
+`/bin/sh',
+`/bin/nsh',
+and
+`/bin/csh'.
+To count the number of persons using each shell one could have issued
+the commands
+.DS
+% grep \-c csh$ /etc/passwd
+27
+% grep \-c nsh$ /etc/passwd
+128
+% grep \-c \-v sh$ /etc/passwd
+430
+%
+.DE
+Since these commands are very similar we can use
+.I foreach
+to do this more easily.
+.DS
+% foreach i (\'sh$\' \'csh$\' \'\-v sh$\')
+? grep \-c $i /etc/passwd
+? end
+27
+128
+430
+%
+.DE
+Note here that the shell prompts for
+input with `? ' when reading the body of the loop.
+.PP
+Very useful with loops are variables which contain lists of filenames
+or other words.
+You can, for example, do
+.DS
+% set a=(\`ls\`)
+% echo $a
+csh.n csh.rm
+% ls
+csh.n
+csh.rm
+% echo $#a
+2
+%
+.DE
+The
+.I set
+command here gave the variable
+.I a
+a list of all the filenames in the current directory as value.
+We can then iterate over these names to perform any chosen function.
+.PP
+The output of a command within `\`' characters is converted by
+the shell to a list of words.
+You can also place the `\`' quoted string within `"' characters
+to take each (non-empty) line as a component of the variable;
+preventing the lines from being split into words at blanks and tabs.
+A modifier `:x' exists which can be used later to expand each component
+of the variable into another variable splitting it into separate words
+at embedded blanks and tabs.
+.NH 2
+Braces { ... } in argument expansion
+.PP
+Another form of filename expansion, alluded
+to before involves the characters `{' and `}'.
+These characters specify that the contained strings, separated by `,'
+are to be consecutively substituted into the containing characters
+and the results expanded left to right.
+Thus
+.DS
+A{str1,str2,...strn}B
+.DE
+expands to
+.DS
+Astr1B Astr2B ... AstrnB
+.DE
+This expansion occurs before the other filename expansions, and may
+be applied recursively (i.e. nested).
+The results of each expanded string are sorted separately, left
+to right order being preserved.
+The resulting filenames are not required to exist if no other expansion
+mechanisms are used.
+This means that this mechanism can be used to generate arguments which are
+not filenames, but which have common parts.
+.PP
+A typical use of this would be
+.DS
+mkdir ~/{hdrs,retrofit,csh}
+.DE
+to make subdirectories `hdrs', `retrofit' and `csh'
+in your home directory.
+This mechanism is most useful when the common prefix is longer
+than in this example, i.e.
+.DS
+chown root /usr/{ucb/{ex,edit},lib/{ex?.?*,how_ex}}
+.DE
+.NH 2
+Command substitution
+.PP
+A command enclosed in `\`' characters is replaced, just before
+filenames are expanded, by the output from that command.
+Thus it is possible to do
+.DS
+set pwd=\`pwd\`
+.DE
+to save the current directory in the variable
+.I pwd
+or to do
+.DS
+ex \`grep \-l TRACE *.c\`
+.DE
+to run the editor
+.I ex
+supplying as arguments those files whose names end in `.c'
+which have the string `TRACE' in them.*
+.FS
+*Command expansion also occurs in input redirected with `<<'
+and within `"' quotations.
+Refer to the shell manual section for full details.
+.FE
+.NH 2
+Other details not covered here
+.PP
+In particular circumstances it may be necessary to know the exact
+nature and order of different substitutions performed by the shell.
+The exact meaning of certain combinations of quotations is also
+occasionally important.
+These are detailed fully in its manual section.
+.PP
+The shell has a number of command line option flags mostly of use
+in writing \s-2UNIX\s0 programs,
+and debugging shell scripts.
+See the csh(1) manual section for a list of these options.
+.bp
diff --git a/share/doc/usd/04.csh/csh.a b/share/doc/usd/04.csh/csh.a
new file mode 100644
index 0000000..22c8f76
--- /dev/null
+++ b/share/doc/usd/04.csh/csh.a
@@ -0,0 +1,93 @@
+.\"-
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)csh.a	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.SH
+Appendix \- Special characters
+.LP
+The following table lists the special characters of
+.I csh
+and the \s-2UNIX\s0 system, giving for each the section(s) in which it
+is discussed.
+A number of these characters also have special meaning in expressions.
+See the
+.I csh
+manual section
+for a complete list.
+.ta .75i 1.5i 2.25i
+.LP
+Syntactic metacharacters
+.DS
+;	2.4	separates commands to be executed sequentially
+|	1.5	separates commands in a pipeline
+( )	2.2,3.6	brackets expressions and variable values
+&	2.5	follows commands to be executed without waiting for completion
+.DE
+.LP
+Filename metacharacters
+.DS
+/	1.6	separates components of a file's pathname
+\&.	1.6	separates root parts of a file name from extensions
+?	1.6	expansion character matching any single character
+*	1.6	expansion character matching any sequence of characters
+[ ]	1.6	expansion sequence matching any single character from a set
+~	1.6	used at the beginning of a filename to indicate home directories
+{ }	4.2	used to specify groups of arguments with common parts
+.DE
+.LP
+Quotation metacharacters
+.DS
+\e	1.7	prevents meta-meaning of following single character
+\'	1.7	prevents meta-meaning of a group of characters
+"	4.3	like \', but allows variable and command expansion
+.DE
+.LP
+Input/output metacharacters
+.DS
+<	1.5	indicates redirected input
+>	1.3	indicates redirected output
+.DE
+.LP
+Expansion/substitution metacharacters
+.DS
+$	3.4	indicates variable substitution
+!	2.3	indicates history substitution
+:	3.6	precedes substitution modifiers
+^	2.3	used in special forms of history substitution
+\`	4.3	indicates command substitution
+.DE
+.LP
+Other metacharacters
+.DS
+#	1.3,3.6	begins scratch file names; indicates shell comments
+\-	1.2	prefixes option (flag) arguments to commands
+%	2.6	prefixes job name specifications
+.DE
+.bp
diff --git a/share/doc/usd/04.csh/csh.g b/share/doc/usd/04.csh/csh.g
new file mode 100644
index 0000000..ba1b161
--- /dev/null
+++ b/share/doc/usd/04.csh/csh.g
@@ -0,0 +1,1719 @@
+.\"-
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
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+.\" modification, are permitted provided that the following conditions
+.\" are met:
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+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
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+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
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+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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+.\"
+.\"	@(#)csh.g	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.SH
+Glossary
+.PP
+This glossary lists the most important terms introduced in the
+introduction to the
+shell and gives references to sections of the shell
+document for further information about them.
+References of the form
+`pr (1)'
+indicate that the command
+.I pr
+is in the \s-2UNIX\s0 User Reference manual in section 1.
+You can look at an online copy of its manual page by doing
+.DS
+man 1 pr
+.DE
+References of the form (2.5)
+indicate that more information can be found in section 2.5 of this
+manual.
+.IP \&\fB.\fR 15n
+Your current directory has the name `.' as well as the name printed
+by the command
+.I pwd;
+see also
+.I dirs.
+The current directory `.' is usually the first
+.I component
+of the search path contained in the variable
+.I path ,
+thus commands which are in `.' are found first (2.2).
+The character `.' is also used in separating
+.I components
+of filenames
+(1.6).
+The character `.' at the beginning of a
+.I component
+of a
+.I pathname
+is treated specially and not matched by the
+.I "filename expansion"
+metacharacters `?', `*', and `[' `]' pairs (1.6).
+.IP \&\fB..\fR
+Each directory has a file `..' in it which is a reference to its
+parent directory.
+After changing into the directory with
+.I chdir ,
+i.e.
+.DS
+chdir paper
+.DE
+you can return to the parent directory by doing
+.DS
+chdir ..
+.DE
+The current directory is printed by
+.I pwd
+(2.7).
+.IP a.out
+Compilers which create executable images create them, by default, in the
+file
+.I a.out.
+for historical reasons (2.3).
+.IP "absolute pathname"
+.br
+A
+.I pathname
+which begins with a `/' is
+.I absolute
+since it specifies the
+.I path
+of directories from the beginning
+of the entire directory system \- called the
+.I root
+directory.
+.I Pathname s
+which are not
+.I absolute
+are called
+.I relative
+(see definition of
+.I "relative pathname" )
+(1.6).
+.IP alias
+An
+.I alias
+specifies a shorter or different name for a \s-2UNIX\s0
+command, or a transformation on a command to be performed in
+the shell.
+The shell has a command
+.I alias
+which establishes
+.I aliases
+and can print their current values.
+The command
+.I unalias
+is used to remove
+.I aliases
+(2.4).
+.IP argument
+Commands in \s-2UNIX\s0 receive a list of
+.I argument
+words.
+Thus the command
+.DS
+echo a b c
+.DE
+consists of the
+.I "command name"
+`echo' and three
+.I argument
+words `a', `b' and `c'.
+The set of
+.I arguments
+after the
+.I "command name"
+is said to be the
+.I "argument list"
+of the command (1.1).
+.IP argv
+The list of arguments to a command written in the shell language
+(a shell script or shell procedure) is stored in a variable called
+.I argv
+within the shell.
+This name is taken from the conventional name in the
+C programming language (3.4).
+.IP background
+Commands started without waiting for them to complete are called
+.I background
+commands (2.6).
+.IP base
+A filename is sometimes thought of as consisting of a
+.I base
+part, before any `.' character, and an
+.I extension
+\- the part after
+the `.'.  See
+.I filename
+and
+.I extension
+(1.6) and basename (1).
+.IP bg
+The
+.I bg
+command causes a
+.I suspended
+job to continue execution in the
+.I background
+(2.6).
+.IP bin
+A directory containing binaries of programs and shell scripts to be
+executed is typically called a
+.I bin
+directory.
+The standard system
+.I bin
+directories are `/bin' containing the most
+heavily used commands and `/usr/bin' which contains most other user
+programs.
+Programs developed at UC Berkeley live in `/usr/ucb', while locally
+written programs live in `/usr/local'.  Games are kept in the directory
+`/usr/games'.
+You can place binaries in any directory.
+If you wish to execute them often, the name of the directories
+should be a
+.I component
+of the variable
+.I path .
+.IP break
+.I Break
+is a builtin command used to exit from loops within the control
+structure of the shell (3.7).
+.IP breaksw
+The
+.I breaksw
+builtin command is used to exit from a
+.I switch
+control structure, like a
+.I break
+exits from loops (3.7).
+.IP builtin
+A command executed directly by the shell is called a
+.I builtin
+command.
+Most commands in \s-2UNIX\s0 are not built into the shell,
+but rather exist as files in
+.I bin
+directories.
+These commands are accessible because the directories in which
+they reside are named in the
+.I path
+variable.
+.IP case
+A
+.I case
+command is used as a label in a
+.I switch
+statement in the shell's control structure, similar to that of the
+language C.
+Details are given in the shell documentation `csh (1)' (3.7).
+.IP cat
+The
+.I cat
+program catenates a list of specified files on the
+.I "standard output" .
+It is usually used to look at the contents of a single file on the terminal,
+to `cat a file' (1.8, 2.3).
+.IP cd
+The
+.I cd
+command is used to change the
+.I "working directory" .
+With no arguments,
+.I cd
+changes your
+.I "working directory"
+to be your
+.I home
+directory (2.4, 2.7).
+.IP chdir
+The
+.I chdir
+command is a synonym for
+.I cd .
+.I Cd
+is usually used because it is easier to type.
+.IP chsh
+The
+.I chsh
+command is used to change the shell which you use on \s-2UNIX\s0.
+By default, you use a different version of the shell
+which resides in `/bin/sh'.
+You can change your shell to `/bin/csh' by doing
+.DS
+chsh your-login-name /bin/csh
+.DE
+Thus I would do
+.DS
+chsh bill /bin/csh
+.DE
+It is only necessary to do this once.
+The next time you log in to \s-2UNIX\s0 after doing this command,
+you will be using
+.I csh
+rather than the shell in `/bin/sh' (1.9).
+.IP cmp
+.I Cmp
+is a program which compares files.
+It is usually used on binary files, or to see if two files are identical (3.6).
+For comparing text files the program
+.I diff ,
+described in `diff (1)' is used.
+.IP command
+A function performed by the system, either by the shell
+(a builtin
+.I command )
+or by a program residing in a file in
+a directory within the \s-2UNIX\s0 system, is called a
+.I command
+(1.1).
+.IP "command name"
+.br
+When a command is issued, it consists of a
+.I "command name" ,
+which is the first word of the command,
+followed by arguments.
+The convention on \s-2UNIX\s0 is that the first word of a
+command names the function to be performed (1.1).
+.IP "command substitution"
+.br
+The replacement of a command enclosed in `\`' characters
+by the text output by that command
+is called
+.I "command substitution"
+(4.3).
+.IP component
+A part of a
+.I pathname
+between `/' characters is called a
+.I component
+of that
+.I pathname .
+A variable
+which has multiple strings as value is said to have
+several
+.I component s;
+each string is a
+.I component
+of the variable.
+.IP continue
+A builtin command which causes execution of the enclosing
+.I foreach
+or
+.I while
+loop to cycle prematurely.
+Similar to the
+.I continue
+command in the programming language C (3.6).
+.IP control-
+Certain special characters, called
+.I control
+characters, are produced by holding down the \s-2CONTROL\s0 key
+on your terminal and simultaneously pressing another character, much like
+the \s-2SHIFT\s0 key is used to produce upper case characters. Thus
+.I control- c
+is produced by holding down the \s-2CONTROL\s0 key while pressing the
+`c' key.  Usually \s-2UNIX\s0 prints a caret (^) followed by the
+corresponding letter when you type a
+.I control
+character (e.g. `^C' for
+.I control- c
+(1.8).
+.IP "core\ dump"
+When a program terminates abnormally, the system places an image
+of its current state in a file named `core'.
+This
+.I "core dump"
+can be examined with the system debugger `adb (1)'
+or `sdb (1)' in order to determine what went wrong with the program (1.8).
+If the shell produces a message of the form
+.DS
+Illegal instruction (core dumped)
+.DE
+(where `Illegal instruction' is only one of several possible
+messages), you should report this to the author of the program
+or a system administrator,
+saving the `core' file.
+.IP cp
+The
+.I cp
+(copy) program is used to copy the contents of one file into another
+file.
+It is one of the most commonly used \s-2UNIX\s0 commands (1.6).
+.IP csh
+The name of the shell
+program that this document describes.
+.IP \&.cshrc
+The file
+.I \&.cshrc
+in your
+.I home
+directory is read by each shell as it begins execution.
+It is usually used to change the setting of the variable
+.I path
+and to set
+.I alias
+parameters which are to take effect globally (2.1).
+.IP cwd
+The
+.I cwd
+variable in the shell holds the
+.I "absolute pathname"
+of the current
+.I "working directory" \&.
+It is changed by the shell whenever your current
+.I "working directory"
+changes and should not be changed otherwise (2.2).
+.IP date
+The
+.I date
+command prints the current date and time (1.3).
+.IP debugging
+.I Debugging
+is the process of correcting mistakes in programs and shell scripts.
+The shell has several options and variables which may be used
+to aid in shell
+.I debugging
+(4.4).
+.IP default:
+The label
+.I default:
+is used within shell
+.I switch
+statements, as it is in the C language
+to label the code to be executed if none of the
+.I case
+labels matches the value switched on (3.7).
+.IP \s-2DELETE\s0
+The
+\s-2DELETE\s0
+or
+\s-2RUBOUT\s0
+key on the terminal normally causes an interrupt to be sent to the current job.
+Many users change the interrupt character to be ^C.
+.IP detached
+A command that continues running in the
+.I background
+after you logout is said to be
+.I detached .
+.IP diagnostic
+An error message produced by a program is often referred to as a
+.I diagnostic .
+Most error messages are not written to the
+.I "standard output" ,
+since that is often directed away from the terminal (1.3, 1.5).
+Error messsages are instead written to the
+.I "diagnostic output"
+which may be directed away from the terminal, but usually is not.
+Thus
+.I diagnostics
+will usually appear on the terminal (2.5).
+.IP directory
+A structure which contains files.
+At any time you are in one particular
+.I directory
+whose names can be printed by the command
+.I pwd .
+The
+.I chdir
+command will change you to another
+.I directory ,
+and make the files
+in that
+.I directory
+visible. The
+.I directory
+in which you are when you first login is your
+.I home
+directory (1.1, 2.7).
+.IP "directory\ stack"
+The shell saves the names of previous
+.I "working directories"
+in the
+.I "directory stack"
+when you change your current
+.I "working directory"
+via the
+.I pushd
+command.  The
+.I "directory stack"
+can be printed by using the
+.I dirs
+command, which includes your current
+.I "working directory"
+as the first directory name on the left (2.7).
+.IP dirs
+The
+.I dirs
+command prints the shell's
+.I "directory stack"
+(2.7).
+.IP du
+The
+.I du
+command is a program (described in `du (1)') which
+prints the number of disk blocks is all directories below
+and including your current
+.I "working directory"
+(2.6).
+.IP echo
+The
+.I echo
+command prints its arguments (1.6, 3.6).
+.IP else
+The
+.I else
+command is part of the `if-then-else-endif' control
+command construct (3.6).
+.IP endif
+If an
+.I if
+statement is ended with the word
+.I then ,
+all lines following the
+.I if
+up to a line starting with the word
+.I endif
+or
+.I else
+are executed if the condition between parentheses after the
+.I if
+is true (3.6).
+.IP \s-2EOF\s0
+An
+.I "end\f1-\fPof\f1-\fPfile"
+is generated by the terminal by a control-d,
+and whenever a command reads to the end of a file which
+it has been given as input.
+Commands receiving input from a
+.I pipe
+receive an
+.I "end\f1-\fPof\f1-\fPfile"
+when the command sending them input completes.
+Most commands terminate when they receive an
+.I "end\f1-\fPof\f1-\fPfile" .
+The shell has an option to ignore
+.I "end\f1-\fPof\f1-\fPfile"
+from a terminal
+input which may help you keep from logging out accidentally
+by typing too many control-d's (1.1, 1.8, 3.8).
+.IP escape
+A character `\e' used to prevent the special meaning of a metacharacter
+is said to
+.I escape
+the character from its special meaning.
+Thus
+.DS
+echo \e*
+.DE
+will echo the character `*' while just
+.DS
+echo *
+.DE
+will echo the names of the file in the current directory.
+In this example, \e
+.I escape s
+`*' (1.7).
+There is also a non-printing character called
+.I escape ,
+usually labelled
+\s-2ESC\s0
+or
+\s-2ALTMODE\s0
+on terminal keyboards.
+Some older \s-2UNIX\s0 systems use this character to indicate that
+output is to be
+.I suspended .
+Most systems use control-s to stop the output and control-q to start it.
+.IP /etc/passwd
+This file contains information about the accounts currently on the
+system.
+It consists of a line for each account with fields separated by
+`:' characters (1.8).
+You can look at this file by saying
+.DS
+cat /etc/passwd
+.DE
+The commands
+.I finger
+and
+.I grep
+are often used to search for information in this file.
+See `finger (1)', `passwd(5)', and `grep (1)' for more details.
+.IP exit
+The
+.I exit
+command is used to force termination of a shell script,
+and is built into the shell (3.9).
+.IP "exit\ status"
+A command which discovers a problem may reflect this back to the command
+(such as a shell) which invoked (executed) it.
+It does this by returning a non-zero number as its
+.I "exit status" ,
+a status of zero being considered
+`normal termination'.
+The
+.I exit
+command can be used to force a shell command script to give a non-zero
+.I "exit status"
+(3.6).
+.IP expansion
+The replacement of strings in the shell input which contain metacharacters
+by other strings is referred to as the process of
+.I expansion .
+Thus the replacement of the word `*' by a sorted list of files
+in the current directory is a `filename expansion'.
+Similarly the replacement of the characters `!!' by the text of
+the last command is a `history expansion'.
+.I Expansions
+are also referred to as
+.I substitutions
+(1.6, 3.4, 4.2).
+.IP expressions
+.I Expressions
+are used in the shell
+to control the conditional structures used in the writing of shell
+scripts and in calculating values for these scripts.
+The operators available in shell
+.I expressions
+are those of the language
+C (3.5).
+.IP extension
+Filenames often consist of a
+.I base
+name and an
+.I extension
+separated by the character `.'.
+By convention, groups of related files often share the same
+.I root
+name.
+Thus if `prog.c' were a C program, then the object file for this
+program would be stored in `prog.o'.
+Similarly a paper written with the
+`\-me'
+nroff macro package might be stored in
+`paper.me'
+while a formatted version of this paper might be kept in
+`paper.out' and a list of spelling errors in
+`paper.errs' (1.6).
+.IP fg
+The
+.I "job control"
+command
+.I fg
+is used to run a
+.I background
+or
+.I suspended
+job in the
+.I foreground
+(1.8, 2.6).
+.IP filename
+Each file in \s-2UNIX\s0 has a name consisting of up to 14 characters
+and not including the character `/' which is used in
+.I pathname
+building.  Most
+.I filenames
+do not begin with the character `.', and contain
+only letters and digits with perhaps a `.' separating the
+.I base
+portion of the
+.I filename
+from an
+.I extension
+(1.6).
+.IP "filename expansion"
+.br
+.I "Filename expansion"
+uses the metacharacters `*', `?' and `[' and `]'
+to provide a convenient mechanism for naming files.
+Using
+.I "filename expansion"
+it is easy to name all the files in
+the current directory, or all files which have a common
+.I root
+name. Other
+.I "filename expansion"
+mechanisms use the metacharacter `~' and allow
+files in other users' directories to be named easily (1.6, 4.2).
+.IP flag
+Many \s-2UNIX\s0 commands accept arguments which are not the names
+of files or other users but are used to modify the action of the commands.
+These are referred to as
+.I flag
+options, and by convention consist of one or more letters preceded by
+the character `\-' (1.2).
+Thus the
+.I ls
+(list files) command has an option
+`\-s' to list the sizes of files.
+This is specified
+.DS
+ls \-s
+.DE
+.IP foreach
+The
+.I foreach
+command is used in shell scripts and at the terminal to specify
+repetition of a sequence of commands while the value of a certain
+shell variable ranges through a specified list (3.6, 4.1).
+.IP foreground
+When commands are executing in the normal way such that the
+shell is waiting for them to finish before prompting for another
+command they are said to be
+.I "foreground jobs"
+or
+.I "running in the foreground" \&.
+This is as opposed to
+.I background .
+.I Foreground
+jobs can be stopped by signals
+from the terminal caused by typing different
+control characters at the keyboard (1.8, 2.6).
+.IP goto
+The shell has a command
+.I goto
+used in shell scripts to transfer control to a given label (3.7).
+.IP grep
+The
+.I grep
+command searches through a list of argument files for a specified string.
+Thus
+.DS
+grep bill /etc/passwd
+.DE
+will print each line in the file
+.I "/etc/passwd"
+which contains the string `bill'.
+Actually,
+.I grep
+scans for
+.I "regular expressions"
+in the sense of the editors
+`ed (1)' and `ex (1)'.
+.I Grep
+stands for
+`globally find
+.I "regular expression"
+and print' (2.4).
+.IP head
+The
+.I head
+command prints the first few lines of one or more files.
+If you have a bunch of files containing text which you are wondering
+about it is sometimes useful to run
+.I head
+with these files as arguments.
+This will usually show enough of what is in these files to let you decide
+which you are interested in (1.5).
+.br
+.I Head
+is also used to describe the part of a
+.I pathname
+before and including the last `/' character.  The
+.I tail
+of a
+.I pathname
+is the part after the last `/'.  The `:h' and `:t' modifiers allow the
+.I head
+or
+.I tail
+of a
+.I pathname
+stored in a shell variable to be used (3.6).
+.IP history
+The
+.I history
+mechanism of the shell allows previous commands to be repeated,
+possibly after modification to correct typing mistakes or to change
+the meaning of the command.
+The shell has a
+.I "history list"
+where these commands are kept, and a
+.I history
+variable which controls how large this list is (2.3).
+.IP "home\ directory"
+.br
+Each user has a
+.I "home directory" ,
+which is given in your entry
+in the password file,
+.I /etc/passwd .
+This is the directory which you are placed in when you first login.
+The
+.I cd
+or
+.I chdir
+command with no arguments takes you back to this directory, whose
+name is recorded in the shell variable
+.I home .
+You can also access the
+.I "home directories"
+of other users in forming
+filenames using a
+.I "filename expansion"
+notation and the character `~' (1.6).
+.IP if
+A conditional command within the shell, the
+.I if
+command is used in shell command scripts to make decisions
+about what course of action to take next (3.6).
+.IP ignoreeof
+Normally, your shell will exit, printing
+`logout'
+if you type a control-d at a prompt of `% '.
+This is the way you usually log off the system.
+You can
+.I set
+the
+.I ignoreeof
+variable if you wish in your
+.I \&.login
+file and then use the command
+.I logout
+to logout.
+This is useful if you sometimes accidentally type too many control-d
+characters, logging yourself off
+(2.2).
+.IP input
+Many commands on \s-2UNIX\s0 take information from the terminal or from
+files which they then act on.
+This information is called
+.I input .
+Commands normally read for
+.I input
+from their
+.I "standard input"
+which is, by default, the terminal.
+This
+.I "standard input"
+can be redirected from a file using a shell metanotation
+with the character `<'.
+Many commands will also read from a file specified as argument.
+Commands placed in
+.I pipelines
+will read from the output of the previous
+command in the
+.I pipeline .
+The leftmost command in a
+.I pipeline
+reads from the terminal if
+you neither redirect its
+.I input
+nor give it a filename to use as
+.I "standard input" .
+Special mechanisms exist for supplying input to commands in shell
+scripts (1.5, 3.8).
+.IP interrupt
+An
+.I interrupt
+is a signal to a program that is generated by typing ^C. (On older versions
+of UNIX the \s-2RUBOUT\s0 or \s-2DELETE\s0 key were used for this purpose.)
+It causes most programs to stop execution.
+Certain programs, such as the shell and the editors,
+handle an
+.I interrupt
+in special ways, usually by stopping what they
+are doing and prompting for another command.
+While the shell is executing another command and waiting for it
+to finish, the shell does not listen to
+.I interrupts.
+The shell often wakes up when you hit
+.I interrupt
+because many commands
+die when they receive an
+.I interrupt
+(1.8, 3.9).
+.IP job
+One or more commands
+typed on the same input line separated by `|' or `;' characters
+are run together and are called a
+.I job \&.
+Simple commands run by themselves without any `|' or `;' characters
+are the simplest
+.I jobs.
+.I Jobs
+are classified as
+.I foreground ,
+.I background ,
+or
+.I suspended
+(2.6).
+.IP "job\ control"
+The builtin functions that control the execution of
+jobs are called
+.I "job control"
+commands.  These are
+.I "bg, fg, stop, kill"
+(2.6).
+.IP "job\ number"
+When each job
+is started it is assigned a small number called a
+.I "job number"
+which is printed next to the job in the output of the
+.I jobs
+command.  This number, preceded by a `%' character, can be used as an argument
+to
+.I "job control"
+commands to indicate
+a specific job (2.6).
+.IP jobs
+The
+.I jobs
+command prints a table showing
+jobs that are either running in the
+.I background
+or are
+.I suspended
+(2.6).
+.IP kill
+A command which sends a
+signal
+to a job causing it to terminate (2.6).
+.IP \&.login
+The file
+.I \&.login
+in your
+.I home
+directory is read by the shell each time you login to \s-2UNIX\s0
+and the commands there are executed.
+There are a number of commands which are usefully placed here,
+especially
+.I set
+commands to the shell itself (2.1).
+.IP "login\ shell"
+The shell that is started on your terminal when you login is called
+your
+.I "login shell" .
+It is different from other shells which you may run (e.g. on
+shell scripts)
+in that it reads the
+.I \&.login
+file before reading commands from the terminal and it reads the
+.I \&.logout
+file after you logout
+(2.1).
+.IP logout
+The
+.I logout
+command causes a login shell to exit.
+Normally, a login shell will exit when you hit control-d
+generating an
+.I end\f1-\fPof\f1-\fPfile,
+but if you have set
+.I ignoreeof
+in you
+.I \&.login
+file then this will not work and you must use
+.I logout
+to log off the \s-2UNIX\s0 system (2.8).
+.IP \&.logout
+When you log off of \s-2UNIX\s0 the shell will execute commands from
+the file
+.I \&.logout
+in your
+.I home
+directory after it prints `logout'.
+.IP lpr
+The command
+.I lpr
+is the line printer daemon.
+The standard input of
+.I lpr
+spooled and printed on the \s-2UNIX\s0 line printer.
+You can also give
+.I lpr
+a list of filenames as arguments to be printed.
+It is most common to use
+.I lpr
+as the last component of a
+.I pipeline
+(2.3).
+.IP ls
+The
+.I ls
+(list files) command is one of the most commonly used \s-2UNIX\s0
+commands.
+With no argument filenames it prints the names of the files in the
+current directory.
+It has a number of useful
+.I flag
+arguments, and can also be given the names of directories
+as arguments, in which case it lists the names of the files in these
+directories (1.2).
+.IP mail
+The
+.I mail
+program is used to send and receive messages from other \s-2UNIX\s0
+users (1.1, 2.1), whether they are logged on or not.
+.IP make
+The
+.I make
+command is used to maintain one or more related files and to
+organize functions to be performed on these files.
+In many ways
+.I make
+is easier to use, and more helpful than
+shell command scripts (3.2).
+.IP makefile
+The file containing commands for
+.I make
+is called
+.I makefile
+or
+.I Makefile
+(3.2).
+.IP manual
+The
+.I manual
+often referred to is the
+`\s-2UNIX\s0 manual'.
+It contains 8 numbered sections with a description of each \s-2UNIX\s0
+program (section 1), system call (section 2), subroutine (section 3),
+device (section 4), special data structure (section 5), game (section 6),
+miscellaneous item (section 7) and system administration program (section 8).
+There are also supplementary documents (tutorials and reference guides)
+for individual programs which require explanation in more detail.
+An online version of the
+.I manual
+is accessible through the
+.I man
+command.
+Its documentation can be obtained online via
+.DS
+man man
+.DE
+If you can't decide what manual page to look in, try the
+.I apropos (1)
+command.
+The supplementary documents are in subdirectories of /usr/doc.
+.IP metacharacter
+.br
+Many characters which are neither letters nor digits have special meaning
+either to the shell or to \s-2UNIX\s0.
+These characters are called
+.I metacharacters .
+If it is necessary to place these characters in arguments to commands
+without them having their special meaning then they must be
+.I quoted .
+An example of a
+.I metacharacter
+is the character `>' which is used
+to indicate placement of output into a file.
+For the purposes of the
+.I history
+mechanism,
+most unquoted
+.I metacharacters
+form separate words (1.4).
+The appendix to this user's manual lists the
+.I metacharacters
+in groups by their function.
+.IP mkdir
+The
+.I mkdir
+command is used to create a new directory.
+.IP modifier
+Substitutions with the
+.I history
+mechanism, keyed by the character `!'
+or of variables using the metacharacter `$', are often subjected
+to modifications, indicated by placing the character `:' after the
+substitution and following this with the
+.I modifier
+itself.
+The
+.I "command substitution"
+mechanism can also be used to perform modification in a similar way,
+but this notation is less clear (3.6).
+.IP more
+The program
+.I more
+writes a file on your terminal allowing you to control how much text
+is displayed at a time.
+.I More
+can move through the file screenful by screenful, line by line,
+search forward for a string, or start again at the beginning of the file.
+It is generally the easiest way of viewing a file (1.8).
+.IP noclobber
+The shell has a variable
+.I noclobber
+which may be set in the file
+.I \&.login
+to prevent accidental destruction of files by the `>' output redirection
+metasyntax of the shell (2.2, 2.5).
+.IP noglob
+The shell variable
+.I noglob
+is set to suppress the
+.I "filename expansion"
+of arguments containing the metacharacters `~', `*', `?', `[' and `]' (3.6).
+.IP notify
+The
+.I notify
+command tells the shell to report on the termination of a specific
+.I "background job"
+at the exact time it occurs as opposed to waiting
+until just before the next prompt to report the termination.
+The
+.I notify
+variable, if set, causes the shell to always report the termination
+of
+.I background
+jobs exactly when they occur (2.6).
+.IP onintr
+The
+.I onintr
+command is built into the shell and is used to control the action
+of a shell command script when an
+.I interrupt
+signal is received (3.9).
+.IP output
+Many commands in \s-2UNIX\s0 result in some lines of text which are
+called their
+.I output.
+This
+.I output
+is usually placed on what is known as the
+.I "standard output"
+which is normally connected to the user's terminal.
+The shell has a syntax using the metacharacter `>' for redirecting
+the
+.I "standard output"
+of a command to a file (1.3).
+Using the
+.I pipe
+mechanism and the metacharacter `|' it is also possible for
+the
+.I "standard output"
+of one command to become the
+.I "standard input"
+of another command (1.5).
+Certain commands such as the line printer daemon
+.I p
+do not place their results on the
+.I "standard output"
+but rather in more
+useful places such as on the line printer (2.3).
+Similarly the
+.I write
+command places its output on another user's terminal rather than its
+.I "standard output"
+(2.3).
+Commands also have a
+.I "diagnostic output"
+where they write their error messages.
+Normally these go to the terminal even if the
+.I "standard output"
+has been sent to a file or another command, but it is possible
+to direct error diagnostics along with
+.I "standard output"
+using a special metanotation (2.5).
+.IP path
+The shell has a variable
+.I path
+which gives the names of the directories in which it searches for
+the commands which it is given.
+It always checks first to see if the command it is given is
+built into the shell.
+If it is, then it need not search for the command as it can do it internally.
+If the command is not builtin, then the shell searches for a file
+with the name given in each of the directories in the
+.I path
+variable, left to right.
+Since the normal definition of the
+.I path
+variable is
+.DS
+path	(. /usr/ucb /bin /usr/bin)
+.DE
+the shell normally looks in the current directory, and then in
+the standard system directories `/usr/ucb', `/bin' and `/usr/bin' for the named
+command (2.2).
+If the command cannot be found the shell will print an error diagnostic.
+Scripts of shell commands will be executed using another shell to interpret
+them if they have `execute' permission set.
+This is normally true because a command of the form
+.DS
+chmod 755 script
+.DE
+was executed to turn this execute permission on (3.3).
+If you add new commands to a directory in the
+.I path ,
+you should issue
+the command
+.I rehash
+(2.2).
+.IP pathname
+A list of names, separated by `/' characters, forms a
+.I pathname.
+Each
+.I component,
+between successive `/' characters, names a directory
+in which the next
+.I component
+file resides.
+.I Pathnames
+which begin with the character `/' are interpreted relative
+to the
+.I root
+directory in the file system.
+Other
+.I pathnames
+are interpreted relative to the current directory
+as reported by
+.I pwd.
+The last component of a
+.I pathname
+may name a directory, but
+usually names a file.
+.IP pipeline
+A group of commands which are connected together, the
+.I "standard output"
+of each connected to the
+.I "standard input"
+of the next,
+is called a
+.I pipeline.
+The
+.I pipe
+mechanism used to connect these commands is indicated by
+the shell metacharacter `|' (1.5, 2.3).
+.IP popd
+The
+.I popd
+command changes the shell's
+.I "working directory"
+to the directory you most recently left using the
+.I pushd
+command.  It returns to the directory without having to type its name,
+forgetting the name of the current
+.I "working directory"
+before doing so (2.7).
+.IP port
+The part of a computer system to which each terminal is
+connected is called a
+.I port .
+Usually the system has a fixed number of
+.I ports ,
+some of which are connected to telephone lines
+for dial-up access, and some of which are permanently
+wired directly to specific terminals.
+.IP pr
+The
+.I pr
+command is used to prepare listings of the contents of files
+with headers giving the name of the file and the date and
+time at which the file was last modified (2.3).
+.IP printenv
+The
+.I printenv
+command is used
+to print the current setting of variables in the environment
+(2.8).
+.IP process
+An instance of a running program is called a
+.I process
+(2.6).
+\s-2UNIX\s0 assigns each
+.I process
+a unique number when it is
+started \- called the
+.I "process number" .
+.I "Process numbers"
+can be used to stop individual
+.I processes
+using the
+.I kill
+or
+.I stop
+commands when the
+.I processes
+are part of a detached
+.I background
+job.
+.IP program
+Usually synonymous with
+.I command ;
+a binary file or shell command script
+which performs a useful function is often
+called a
+.I program .
+.IP prompt
+Many programs will print a
+.I prompt
+on the terminal when they expect input.
+Thus the editor
+`ex (1)' will print a `:' when it expects input.
+The shell
+.I prompts
+for input with `% ' and occasionally with `? ' when
+reading commands from the terminal (1.1).
+The shell has a variable
+.I prompt
+which may be set to a different value to change the shell's main
+.I prompt .
+This is mostly used when debugging the shell (2.8).
+.IP pushd
+The
+.I pushd
+command, which means `push directory', changes the shell's
+.I "working directory"
+and also remembers the current
+.I "working directory"
+before the change is made, allowing you to return to the same
+directory via the
+.I popd
+command later without retyping its name (2.7).
+.IP ps
+The
+.I ps
+command is used to show the processes you are currently running.
+Each process is shown with its unique process number,
+an indication of the terminal name it is attached to,
+an indication of the state of the process (whether it is running,
+stopped, awaiting some event (sleeping), and whether it is swapped out),
+and the amount of \s-2CPU\s0 time it has used so far.
+The command is identified by printing some of the words used
+when it was invoked (2.6).
+Shells, such as the
+.I csh
+you use to run the
+.I ps
+command, are not normally shown in the output.
+.IP pwd
+The
+.I pwd
+command prints the full
+.I pathname
+of the current
+.I "working directory" \&.
+The
+.I dirs
+builtin command is usually a better and faster choice.
+.IP quit
+The
+.I quit
+signal, generated by a control-\e,
+is used to terminate programs which are behaving unreasonably.
+It normally produces a core image file (1.8).
+.IP quotation
+The process by which metacharacters are prevented their special
+meaning, usually by using the character `\' in pairs, or by
+using the character `\e', is referred to as
+.I quotation
+(1.7).
+.IP redirection
+The routing of input or output from or to a file is known
+as
+.I redirection
+of input or output (1.3).
+.IP rehash
+The
+.I rehash
+command tells the shell to rebuild its internal table of which commands
+are found in which directories in your
+.I path .
+This is necessary when a new program is installed in one of these
+directories (2.8).
+.IP "relative pathname"
+.br
+A
+.I pathname
+which does not begin with a `/' is called a
+.I "relative pathname"
+since it is interpreted
+.I relative
+to the current
+.I "working directory" .
+The first
+.I component
+of such a
+.I pathname
+refers to some file or directory in the
+.I "working directory" ,
+and subsequent
+.I components
+between `/' characters refer to directories below the
+.I "working directory" .
+.I Pathnames
+that are not
+.I relative
+are called
+.I "absolute pathnames"
+(1.6).
+.IP repeat
+The
+.I repeat
+command iterates another command a specified number of times.
+.IP root
+The directory
+that is at the top of the entire directory structure is called the
+.I root
+directory since it is the `root' of the entire tree structure of
+directories.  The name used in
+.I pathnames
+to indicate the
+.I root
+is `/'.
+.I Pathnames
+starting with `/' are said to be
+.I absolute
+since they start at the
+.I root
+directory.
+.I Root
+is also used as the part of a
+.I pathname
+that is left after removing
+the
+.I extension .
+See
+.I filename
+for a further explanation (1.6).
+.IP \s-2RUBOUT\s0
+The \s-2RUBOUT\s0 or \s-2DELETE\s0
+key is often used to erase the previously typed character; some users
+prefer the \s-2BACKSPACE\s0 for this purpose.  On older versions of \s-2UNIX\s0
+this key served as the \s-2INTR\s0 character.
+.IP "scratch file"
+Files whose names begin with a `#' are referred to as
+.I "scratch files" ,
+since they are automatically removed by the system after a couple of
+days of non-use, or more frequently if disk space becomes tight (1.3).
+.IP script
+Sequences of shell commands placed in a file are called shell command
+.I scripts .
+It is often possible to perform simple tasks using these
+.I scripts
+without writing a program in a language such as C, by
+using the shell to selectively run other programs (3.3, 3.10).
+.IP set
+The builtin
+.I set
+command is used to assign new values to shell variables
+and to show the values of the current variables.
+Many shell variables have special meaning to the shell itself.
+Thus by using the
+.I set
+command the behavior of the shell can be affected (2.1).
+.IP setenv
+Variables in the environment `environ (5)'
+can be changed by using the
+.I setenv
+builtin command (2.8).
+The
+.I printenv
+command can be used to print the value of the variables in the environment.
+.IP shell
+A
+.I shell
+is a command language interpreter.
+It is possible to write and run your own
+.I shell ,
+as
+.I shells
+are no different than any other programs as far as the
+system is concerned.
+This manual deals with the details of one particular
+.I shell ,
+called
+.I csh.
+.IP "shell script"
+See
+.I script
+(3.3, 3.10).
+.IP signal
+A
+.I signal
+in \s-2UNIX\s0 is a short message that is sent to a running program
+which causes something to happen to that process.
+.I Signals
+are sent either by typing special
+.I control
+characters on the keyboard or by using the
+.I kill
+or
+.I stop
+commands (1.8, 2.6).
+.IP sort
+The
+.I sort
+program sorts a sequence of lines in ways that can be controlled
+by argument
+.I flags
+(1.5).
+.IP source
+The
+.I source
+command causes the shell to read commands from a specified file.
+It is most useful for reading files such as
+.I \&.cshrc
+after changing them (2.8).
+.IP "special character"
+.br
+See
+.I metacharacters
+and the
+appendix to this manual.
+.IP standard
+We refer often to the
+.I "standard input"
+and
+.I "standard output"
+of commands.
+See
+.I input
+and
+.I output
+(1.3, 3.8).
+.IP status
+A command normally returns a
+.I status
+when it finishes.
+By convention a
+.I status
+of zero indicates that the command succeeded.
+Commands may return non-zero
+.I status
+to indicate that some abnormal event has occurred.
+The shell variable
+.I status
+is set to the
+.I status
+returned by the last command.
+It is most useful in shell commmand scripts (3.6).
+.IP stop
+The
+.I stop
+command causes a
+.I background
+job to become
+.I suspended
+(2.6).
+.IP string
+A sequential group of characters taken together is called a
+.I string \&.
+.I Strings
+can contain any printable characters (2.2).
+.IP stty
+The
+.I stty
+program changes certain parameters inside \s-2UNIX\s0 which determine
+how your terminal is handled.  See `stty (1)' for a complete description (2.6).
+.IP substitution
+The shell implements a number of
+.I substitutions
+where sequences indicated by metacharacters are replaced by other sequences.
+Notable examples of this are history
+.I substitution
+keyed by the
+metacharacter `!' and variable
+.I substitution
+indicated by `$'.
+We also refer to
+.I substitutions
+as
+.I expansions
+(3.4).
+.IP suspended
+A job becomes
+.I suspended
+after a \s-2STOP\s0 signal is sent to it, either by typing a
+.I control -z
+at the terminal (for
+.I foreground
+jobs) or by using the
+.I stop
+command (for
+.I background
+jobs).  When
+.I suspended ,
+a job temporarily stops running until it is restarted by either the
+.I fg
+or
+.I bg
+command (2.6).
+.IP switch
+The
+.I switch
+command of the shell allows the shell
+to select one of a number of sequences of commands based on an
+argument string.
+It is similar to the
+.I switch
+statement in the language C (3.7).
+.IP termination
+When a command which is being executed finishes we say it undergoes
+.I termination
+or
+.I terminates.
+Commands normally terminate when they read an
+.I end\f1-\fPof\f1-\fPfile
+from their
+.I "standard input" .
+It is also possible to terminate commands by sending them
+an
+.I interrupt
+or
+.I quit
+signal (1.8).
+The
+.I kill
+program terminates specified jobs (2.6).
+.IP then
+The
+.I then
+command is part of the shell's
+`if-then-else-endif' control construct used in command scripts (3.6).
+.IP time
+The
+.I time
+command can be used to measure the amount of \s-2CPU\s0
+and real time consumed by a specified command as well
+as the amount of disk i/o, memory utilized, and number
+of page faults and swaps taken by the command (2.1, 2.8).
+.IP tset
+The
+.I tset
+program is used to set standard erase and kill characters
+and to tell the system what kind of terminal you are using.
+It is often invoked in a
+.I \&.login
+file (2.1).
+.IP tty
+The word
+.I tty
+is a historical abbreviation for `teletype' which is frequently used
+in \s-2UNIX\s0 to indicate the
+.I port
+to which a given terminal is connected.  The
+.I tty
+command will print the name of the
+.I tty
+or
+.I port
+to which your terminal is presently connected.
+.IP unalias
+The
+.I unalias
+command removes aliases (2.8).
+.IP \s-2UNIX\s0
+\s-2UNIX\s0 is an operating system on which
+.I csh
+runs.
+\s-2UNIX\s0 provides facilities which allow
+.I csh
+to invoke other programs such as editors and text formatters which
+you may wish to use.
+.IP unset
+The
+.I unset
+command removes the definitions of shell variables (2.2, 2.8).
+.IP "variable expansion"
+.br
+See
+.I variables
+and
+.I expansion
+(2.2, 3.4).
+.IP variables
+.I Variables
+in
+.I csh
+hold one or more strings as value.
+The most common use of
+.I variables
+is in controlling the behavior
+of the shell.
+See
+.I path ,
+.I noclobber ,
+and
+.I ignoreeof
+for examples.
+.I Variables
+such as
+.I argv
+are also used in writing shell programs (shell command scripts)
+(2.2).
+.IP verbose
+The
+.I verbose
+shell variable can be set to cause commands to be echoed
+after they are history expanded.
+This is often useful in debugging shell scripts.
+The
+.I verbose
+variable is set by the shell's
+.I \-v
+command line option (3.10).
+.IP wc
+The
+.I wc
+program calculates the number of characters, words, and lines in the
+files whose names are given as arguments (2.6).
+.IP while
+The
+.I while
+builtin control construct is used in shell command scripts (3.7).
+.IP word
+A sequence of characters which forms an argument to a command is called
+a
+.I word .
+Many characters which are neither letters, digits, `\-', `.' nor `/'
+form
+.I words
+all by themselves even if they are not surrounded
+by blanks.
+Any sequence of characters may be made into a
+.I word
+by surrounding it
+with `\'' characters
+except for the characters `\'' and `!' which require special treatment
+(1.1).
+This process of placing special characters in
+.I words
+without their special meaning is called
+.I quoting .
+.IP "working directory"
+.br
+At any given time you are in one particular directory, called
+your
+.I "working directory" .
+This directory's name is printed by the
+.I pwd
+command and the files listed by
+.I ls
+are the ones in this directory.
+You can change
+.I "working directories"
+using
+.I chdir .
+.IP write
+The
+.I write
+command is an obsolete way of communicating with other users who are logged in to
+\s-2UNIX\s0 (you have to take turns typing).  If you are both using display
+terminals, use \fItalk\fP(1), which is much more pleasant.
diff --git a/share/doc/usd/04.csh/tabs b/share/doc/usd/04.csh/tabs
new file mode 100644
index 0000000..196d437
--- /dev/null
+++ b/share/doc/usd/04.csh/tabs
@@ -0,0 +1,32 @@
+.\"-
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)tabs	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.ta 5n 10n 15n 20n 25n 30n 35n 40n 45n 50n 55n 60n 65n 70n 75n 80n
diff --git a/share/doc/usd/05.dc/Makefile b/share/doc/usd/05.dc/Makefile
index 2b01e0c..fd1cffc 100644
--- a/share/doc/usd/05.dc/Makefile
+++ b/share/doc/usd/05.dc/Makefile
@@ -4,6 +4,5 @@
 VOLUME=	usd/05.dc
 SRCS=	dc
 MACROS=	-ms
-SRCDIR=	${.CURDIR}/../../../../usr.bin/dc/USD.doc
 
 .include <bsd.doc.mk>
diff --git a/share/doc/usd/05.dc/dc b/share/doc/usd/05.dc/dc
new file mode 100644
index 0000000..4caa0f4
--- /dev/null
+++ b/share/doc/usd/05.dc/dc
@@ -0,0 +1,753 @@
+.\"	$FreeBSD$
+.\"	$OpenBSD: dc,v 1.2 2003/09/22 19:08:27 otto Exp $
+.\"
+.\" Copyright (C) Caldera International Inc.  2001-2002.
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code and documentation must retain the above
+.\"    copyright notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed or owned by Caldera
+.\"	International, Inc.
+.\" 4. Neither the name of Caldera International, Inc. nor the names of other
+.\"    contributors may be used to endorse or promote products derived from
+.\"    this software without specific prior written permission.
+.\"
+.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
+.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT,
+.\" INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+.\" POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\"	@(#)dc	8.1 (Berkeley) 6/8/93
+.\"
+.EH 'USD:5-%''DC \- An Interactive Desk Calculator'
+.OH 'DC \- An Interactive Desk Calculator''USD:5-%'
+.\".RP
+.\" ....TM 75-1271-8 39199 39199-11
+.ND
+.TL
+DC \- An Interactive Desk Calculator
+.AU "MH 2C-524" 3878
+Robert Morris
+.AU
+Lorinda Cherry
+.AI
+.\" .MH
+.AB
+DC is an interactive desk calculator program implemented
+on the
+.UX
+time-sharing system to do arbitrary-precision
+integer arithmetic.
+It has provision for manipulating scaled fixed-point numbers and
+for input and output in bases other than decimal.
+.PP
+The size of numbers that can be manipulated is limited
+only by available core storage.
+On typical implementations of
+.UX ,
+the size of numbers that
+can be handled varies from several hundred digits on the smallest
+systems to several thousand on the largest.
+.AE
+.PP
+.SH
+.PP
+.ft I
+Editor's note: the description of the implementation details of DC in this
+paper is only valid for the original version of DC.
+The current version of DC uses a different approach.
+.ft
+.PP
+DC is an arbitrary precision arithmetic package implemented
+on the
+.UX
+time-sharing system
+in the form of an interactive desk calculator.
+It works like a stacking calculator using reverse Polish notation.
+Ordinarily DC operates on decimal integers, but one may
+specify an input base, output base, and a number of fractional
+digits to be maintained.
+.PP
+A language called BC [1] has been developed which accepts
+programs written in the familiar style of higher-level
+programming languages and compiles output which is
+interpreted by DC.
+Some of the commands described below were designed
+for the compiler interface and are not easy for a human user
+to manipulate.
+.PP
+Numbers that are typed into DC are put on a push-down
+stack.
+DC commands work by taking the top number or two
+off the stack, performing the desired operation, and pushing the result
+on the stack.
+If an argument is given,
+input is taken from that file until its end,
+then from the standard input.
+.SH
+SYNOPTIC DESCRIPTION
+.PP
+Here we describe the DC commands that are intended
+for use by people.  The additional commands that are
+intended to be invoked by compiled output are
+described in the detailed description.
+.PP
+Any number of commands are permitted on a line.
+Blanks and new-line characters are ignored except within numbers
+and in places where a register name is expected.
+.PP
+The following constructions are recognized:
+.SH
+number
+.IP
+The value of the number is pushed onto the main stack.
+A number is an unbroken string of the digits 0-9
+and the capital letters A\-F which are treated as digits
+with values 10\-15 respectively.
+The number may be preceded by an underscore _ to input a
+negative number.
+Numbers may contain decimal points.
+.SH
++  \-  *  %  ^
+.IP
+The
+top two values on the stack are added
+(\fB+\fP),
+subtracted
+(\fB\-\fP),
+multiplied (\fB*\fP),
+divided (\fB/\fP),
+remaindered (\fB%\fP),
+or exponentiated (^).
+The two entries are popped off the stack;
+the result is pushed on the stack in their place.
+The result of a division is an integer truncated toward zero.
+See the detailed description below for the treatment of
+numbers with decimal points.
+An exponent must not have any digits after the decimal point.
+.SH
+s\fIx\fP
+.IP
+The
+top of the main stack is popped and stored into
+a register named \fIx\fP, where \fIx\fP may be any character.
+If
+the
+.ft B
+s
+.ft
+is capitalized,
+.ft I
+x
+.ft
+is treated as a stack and the value is pushed onto it.
+Any character, even blank or new-line, is a valid register name.
+.SH
+l\fIx\fP
+.IP
+The
+value in register
+.ft I
+x
+.ft
+is pushed onto the stack.
+The register
+.ft I
+x
+.ft
+is not altered.
+If the
+.ft B
+l
+.ft
+is capitalized,
+register
+.ft I
+x
+.ft
+is treated as a stack and its top value is popped onto the main stack.
+.LP
+All registers start with empty value which is treated as a zero
+by the command \fBl\fP and is treated as an error by the command \fBL\fP.
+.SH
+d
+.IP
+The
+top value on the stack is duplicated.
+.SH
+p
+.IP
+The top value on the stack is printed.
+The top value remains unchanged.
+.SH
+f
+.IP
+All values on the stack and in registers are printed.
+.SH
+x
+.IP
+treats the top element of the stack as a character string,
+removes it from the stack, and
+executes it as a string of DC commands.
+.SH
+[ ... ]
+.IP
+puts the bracketed character string onto the top of the stack.
+.SH
+q
+.IP
+exits the program.
+If executing a string, the recursion level is
+popped by two.
+If
+.ft B
+q
+.ft
+is capitalized,
+the top value on the stack is popped and the string execution level is popped
+by that value.
+.SH
+<\fIx\fP  >\fIx\fP  =\fIx\fP  !<\fIx\fP  !>\fIx\fP  !=\fIx\fP
+.IP
+The
+top two elements of the stack are popped and compared.
+Register
+.ft I
+x
+.ft
+is executed if they obey the stated
+relation.
+Exclamation point is negation.
+.SH
+v
+.IP
+replaces the top element on the stack by its square root.
+The square root of an integer is truncated to an integer.
+For the treatment of numbers with decimal points, see
+the detailed description below.
+.SH
+!
+.IP
+interprets the rest of the line as a
+.UX
+command.
+Control returns to DC when the
+.UX
+command terminates.
+.SH
+c
+.IP
+All values on the stack are popped; the stack becomes empty.
+.SH
+i
+.IP
+The top value on the stack is popped and used as the
+number radix for further input.
+If \fBi\fP is capitalized, the value of
+the input base is pushed onto the stack.
+No mechanism has been provided for the input of arbitrary
+numbers in bases less than 1 or greater than 16.
+.SH
+o
+.IP
+The top value on the stack is popped and used as the
+number radix for further output.
+If \fBo\fP is capitalized, the value of the output
+base is pushed onto the stack.
+.SH
+k
+.IP
+The top of the stack is popped, and that value is used as
+a scale factor
+that influences the number of decimal places
+that are maintained during multiplication, division, and exponentiation.
+The scale factor must be greater than or equal to zero and
+less than 100.
+If \fBk\fP is capitalized, the value of the scale factor
+is pushed onto the stack.
+.SH
+z
+.IP
+The value of the stack level is pushed onto the stack.
+.SH
+?
+.IP
+A line of input is taken from the input source (usually the console)
+and executed.
+.SH
+DETAILED DESCRIPTION
+.SH
+Internal Representation of Numbers
+.PP
+Numbers are stored internally using a dynamic storage allocator.
+Numbers are kept in the form of a string
+of digits to the base 100 stored one digit per byte
+(centennial digits).
+The string is stored with the low-order digit at the
+beginning of the string.
+For example, the representation of 157
+is 57,1.
+After any arithmetic operation on a number, care is taken
+that all digits are in the range 0\-99 and that
+the number has no leading zeros.
+The number zero is represented by the empty string.
+.PP
+Negative numbers are represented in the 100's complement
+notation, which is analogous to two's complement notation for binary
+numbers.
+The high order digit of a negative number is always \-1
+and all other digits are in the range 0\-99.
+The digit preceding the high order \-1 digit is never a 99.
+The representation of \-157 is 43,98,\-1.
+We shall call this the canonical form of a number.
+The advantage of this kind of representation of negative
+numbers is ease of addition.  When addition is performed digit
+by digit, the result is formally correct.  The result need only
+be modified, if necessary, to put it into canonical form.
+.PP
+Because the largest valid digit is 99 and the byte can
+hold numbers twice that large, addition can be carried out
+and the handling of carries done later when
+that is convenient, as it sometimes is.
+.PP
+An additional byte is stored with each number beyond
+the high order digit to indicate the number of
+assumed decimal digits after the decimal point.  The representation
+of .001 is 1,\fI3\fP
+where the scale has been italicized to emphasize the fact that it
+is not the high order digit.
+The value of this extra byte is called the
+.ft B
+scale factor
+.ft
+of the number.
+.SH
+The Allocator
+.PP
+DC uses a dynamic string storage allocator
+for all of its internal storage.
+All reading and writing of numbers internally is done through
+the allocator.
+Associated with each string in the allocator is a four-word header containing pointers
+to the beginning of the string, the end of the string,
+the next place to write, and the next place to read.
+Communication between the allocator and DC
+is done via pointers to these headers.
+.PP
+The allocator initially has one large string on a list
+of free strings.  All headers except the one pointing
+to this string are on a list of free headers.
+Requests for strings are made by size.
+The size of the string actually supplied is the next higher
+power of 2.
+When a request for a string is made, the allocator
+first checks the free list to see if there is
+a string of the desired size.
+If none is found, the allocator finds the next larger free string and splits it repeatedly until
+it has a string of the right size.
+Left-over strings are put on the free list.
+If there are no larger strings,
+the allocator tries to coalesce smaller free strings into
+larger ones.
+Since all strings are the result
+of splitting large strings,
+each string has a neighbor that is next to it in core
+and, if free, can be combined with it to make a string twice as long.
+This is an implementation of the `buddy system' of allocation
+described in [2].
+.PP
+Failing to find a string of the proper length after coalescing,
+the allocator asks the system for more space.
+The amount of space on the system is the only limitation
+on the size and number of strings in DC.
+If at any time in the process of trying to allocate a string, the allocator runs out of
+headers, it also asks the system for more space.
+.PP
+There are routines in the allocator for reading, writing, copying, rewinding,
+forward-spacing, and backspacing strings.
+All string manipulation is done using these routines.
+.PP
+The reading and writing routines
+increment the read pointer or write pointer so that
+the characters of a string are read or written in
+succession by a series of read or write calls.
+The write pointer is interpreted as the end of the
+information-containing portion of a string and a call
+to read beyond that point returns an end-of-string indication.
+An attempt to write beyond the end of a string
+causes the allocator to
+allocate a larger space and then copy
+the old string into the larger block.
+.SH
+Internal Arithmetic
+.PP
+All arithmetic operations are done on integers.
+The operands (or operand) needed for the operation are popped
+from the main stack and their scale factors stripped off.
+Zeros are added or digits removed as necessary to get
+a properly scaled result from the internal arithmetic routine.
+For example, if the scale of the operands is different and decimal
+alignment is required, as it is for
+addition, zeros are appended to the operand with the smaller
+scale.
+After performing the required arithmetic operation,
+the proper scale factor is appended to the end of the number before
+it is pushed on the stack.
+.PP
+A register called \fBscale\fP plays a part
+in the results of most arithmetic operations.
+\fBscale\fP is the bound on the number of decimal places retained in
+arithmetic computations.
+\fBscale\fP may be set to the number on the top of the stack
+truncated to an integer with the \fBk\fP command.
+\fBK\fP may be used to push the value of \fBscale\fP on the stack.
+\fBscale\fP must be greater than or equal to 0 and less than 100.
+The descriptions of the individual arithmetic operations will
+include the exact effect of \fBscale\fP on the computations.
+.SH
+Addition and Subtraction
+.PP
+The scales of the two numbers are compared and trailing
+zeros are supplied to the number with the lower scale to give both
+numbers the same scale.  The number with the smaller scale is
+multiplied by 10 if the difference of the scales is odd.
+The scale of the result is then set to the larger of the scales
+of the two operands.
+.PP
+Subtraction is performed by negating the number
+to be subtracted and proceeding as in addition.
+.PP
+Finally, the addition is performed digit by digit from the
+low order end of the number.  The carries are propagated
+in the usual way.
+The resulting number is brought into canonical form, which may
+require stripping of leading zeros, or for negative numbers
+replacing the high-order configuration 99,\-1 by the digit \-1.
+In any case, digits which are not in the range 0\-99 must
+be brought into that range, propagating any carries or borrows
+that result.
+.SH
+Multiplication
+.PP
+The scales are removed from the two operands and saved.
+The operands are both made positive.
+Then multiplication is performed in
+a digit by digit manner that exactly mimics the hand method
+of multiplying.
+The first number is multiplied by each digit of the second
+number, beginning with its low order digit.  The intermediate
+products are accumulated into a partial sum which becomes the
+final product.
+The product is put into the canonical form and its sign is
+computed from the signs of the original operands.
+.PP
+The scale of the result is set equal to the sum
+of the scales of the two operands.
+If that scale is larger than the internal register
+.ft B
+scale
+.ft
+and also larger than both of the scales of the two operands,
+then the scale of the result is set equal to the largest
+of these three last quantities.
+.SH
+Division
+.PP
+The scales are removed from the two operands.
+Zeros are appended or digits removed from the dividend to make
+the scale of the result of the integer division equal to
+the internal quantity
+\fBscale\fP.
+The signs are removed and saved.
+.PP
+Division is performed much as it would be done by hand.
+The difference of the lengths of the two numbers
+is computed.
+If the divisor is longer than the dividend,
+zero is returned.
+Otherwise the top digit of the divisor is divided into the top
+two digits of the dividend.
+The result is used as the first (high-order) digit of the
+quotient.
+It may turn out be one unit too low, but if it is, the next
+trial quotient will be larger than 99 and this will be
+adjusted at the end of the process.
+The trial digit is multiplied by the divisor and the result subtracted
+from the dividend and the process is repeated to get
+additional quotient digits until the remaining
+dividend is smaller than the divisor.
+At the end, the digits of the quotient are put into
+the canonical form, with propagation of carry as needed.
+The sign is set from the sign of the operands.
+.SH
+Remainder
+.PP
+The division routine is called and division is performed
+exactly as described.  The quantity returned is the remains of the
+dividend at the end of the divide process.
+Since division truncates toward zero, remainders have the same
+sign as the dividend.
+The scale of the remainder is set to 
+the maximum of the scale of the dividend and
+the scale of the quotient plus the scale of the divisor.
+.SH
+Square Root
+.PP
+The scale is stripped from the operand.
+Zeros are added if necessary to make the
+integer result have a scale that is the larger of
+the internal quantity
+\fBscale\fP
+and the scale of the operand.
+.PP
+The method used to compute sqrt(y) is Newton's method
+with successive approximations by the rule
+.EQ
+x sub {n+1} ~=~ half ( x sub n + y over x sub n )
+.EN
+The initial guess is found by taking the integer square root
+of the top two digits.
+.SH
+Exponentiation
+.PP
+Only exponents with zero scale factor are handled.  If the exponent is
+zero, then the result is 1.  If the exponent is negative, then
+it is made positive and the base is divided into one.  The scale
+of the base is removed.
+.PP
+The integer exponent is viewed as a binary number.
+The base is repeatedly squared and the result is
+obtained as a product of those powers of the base that
+correspond to the positions of the one-bits in the binary
+representation of the exponent.
+Enough digits of the result
+are removed to make the scale of the result the same as if the
+indicated multiplication had been performed.
+.SH
+Input Conversion and Base
+.PP
+Numbers are converted to the internal representation as they are read
+in.
+The scale stored with a number is simply the number of fractional digits input.
+Negative numbers are indicated by preceding the number with a \fB\_\fP (an 
+underscore).
+The hexadecimal digits A\-F correspond to the numbers 10\-15 regardless of input base.
+The \fBi\fP command can be used to change the base of the input numbers.
+This command pops the stack, truncates the resulting number to an integer,
+and uses it as the input base for all further input.
+The input base is initialized to 10 but may, for example be changed to
+8 or 16 to do octal or hexadecimal to decimal conversions.
+The command \fBI\fP will push the value of the input base on the stack.
+.SH
+Output Commands
+.PP
+The command \fBp\fP causes the top of the stack to be printed.
+It does not remove the top of the stack.
+All of the stack and internal registers can be output
+by typing the command \fBf\fP.
+The \fBo\fP command can be used to change the output base.
+This command uses the top of the stack, truncated to an integer as
+the base for all further output.
+The output base in initialized to 10.
+It will work correctly for any base.
+The command \fBO\fP pushes the value of the output base on the stack.
+.SH
+Output Format and Base
+.PP
+The input and output bases only affect
+the interpretation of numbers on input and output; they have no
+effect on arithmetic computations.
+Large numbers are output with 70 characters per line;
+a \\ indicates a continued line.
+All choices of input and output bases work correctly, although not all are
+useful.
+A particularly useful output base is 100000, which has the effect of
+grouping digits in fives.
+Bases of 8 and 16 can be used for decimal-octal or decimal-hexadecimal
+conversions.
+.SH
+Internal Registers
+.PP
+Numbers or strings may be stored in internal registers or loaded on the stack
+from registers with the commands \fBs\fP and \fBl\fP.
+The command \fBs\fIx\fR pops the top of the stack and
+stores the result in register \fBx\fP.
+\fIx\fP can be any character.
+\fBl\fIx\fR puts the contents of register \fBx\fP on the top of the stack.
+The \fBl\fP command has no effect on the contents of register \fIx\fP.
+The \fBs\fP command, however, is destructive.
+.SH
+Stack Commands
+.PP
+The command \fBc\fP clears the stack.
+The command \fBd\fP pushes a duplicate of the number on the top of the stack
+on the stack.
+The command \fBz\fP pushes the stack size on the stack.
+The command \fBX\fP replaces the number on the top of the stack
+with its scale factor.
+The command \fBZ\fP replaces the top of the stack
+with its length.
+.SH
+Subroutine Definitions and Calls
+.PP
+Enclosing a string in \fB[ ]\fP pushes the ascii string on the stack.
+The \fBq\fP command quits or in executing a string, pops the recursion levels by two.
+.SH
+Internal Registers \- Programming DC
+.PP
+The load and store
+commands together with \fB[ ]\fP to store strings, \fBx\fP to execute
+and the testing commands `<', `>', `=', `!<', `!>', `!=' can be used to program
+DC.
+The \fBx\fP command assumes the top of the stack is an string of DC commands
+and executes it.
+The testing commands compare the top two elements on the stack and if the relation holds, execute the register
+that follows the relation.
+For example, to print the numbers 0-9,
+.DS
+[lip1+  si  li10>a]sa
+0si  lax
+.DE
+.SH
+Push-Down Registers and Arrays
+.PP
+These commands were designed for used by a compiler, not by
+people.
+They involve push-down registers and arrays.
+In addition to the stack that commands work on, DC can be thought
+of as having individual stacks for each register.
+These registers are operated on by the commands \fBS\fP and \fBL\fP.
+\fBS\fIx\fR pushes the top value of the main stack onto the stack for
+the register \fIx\fP.
+\fBL\fIx\fR pops the stack for register \fIx\fP and puts the result on the main
+stack.
+The commands \fBs\fP and \fBl\fP also work on registers but not as push-down
+stacks.
+\fBl\fP doesn't effect the top of the
+register stack, and \fBs\fP destroys what was there before.
+.PP
+The commands to work on arrays are \fB:\fP and \fB;\fP.
+\fB:\fIx\fR pops the stack and uses this value as an index into
+the array \fIx\fP.
+The next element on the stack is stored at this index in \fIx\fP.
+An index must be greater than or equal to 0 and
+less than 2048.
+\fB;\fIx\fR is the command to load the main stack from the array \fIx\fP.
+The value on the top of the stack is the index
+into the array \fIx\fP of the value to be loaded.
+.SH
+Miscellaneous Commands
+.PP
+The command \fB!\fP interprets the rest of the line as a 
+.UX 
+command and passes it to 
+.UX
+to execute.
+One other compiler command is \fBQ\fP.
+This command uses the top of the stack as the number of levels of recursion to skip.
+.SH
+DESIGN CHOICES
+.PP
+The real reason for the use of a dynamic storage allocator was
+that a general purpose program could be (and in fact has been)
+used for a variety of other tasks.
+The allocator has some value for input and for compiling (i.e.
+the bracket [...] commands) where it cannot be known in advance
+how long a string will be.
+The result was that at a modest
+cost in execution time, all considerations of string allocation
+and sizes of strings were removed from the remainder of the program
+and debugging was made easier.  The allocation method
+used wastes approximately 25% of available space.
+.PP
+The choice of 100 as a base for internal arithmetic
+seemingly has no compelling advantage.  Yet the base cannot
+exceed 127 because of hardware limitations and at the cost
+of 5% in space, debugging was made a great deal easier and
+decimal output was made much faster.
+.PP
+The reason for a stack-type arithmetic design was
+to permit all DC commands from addition to subroutine execution
+to be implemented in essentially the same way.  The result
+was a considerable degree of logical separation of the final
+program into modules with very little communication between
+modules.
+.PP
+The rationale for the lack of interaction between the scale and the bases
+was to provide an understandable means of proceeding after
+a change of base or scale when numbers had already been entered.
+An earlier implementation which had global notions of
+scale and base did not work out well.
+If the value of
+.ft B
+scale
+.ft
+were to be interpreted in the current
+input or output base,
+then a change of base or scale in the midst of a
+computation would cause great confusion in the interpretation
+of the results.
+The current scheme has the advantage that the value of
+the input and output bases
+are only used for input and output, respectively, and they
+are ignored in all other operations.
+The value of
+scale
+is not used for any essential purpose by any part of the program
+and it is used only to prevent the number of
+decimal places resulting from the arithmetic operations from
+growing beyond all bounds.
+.PP
+The design rationale for the choices for the scales of
+the results of arithmetic were that in no case should
+any significant digits be thrown away if, on appearances, the
+user actually wanted them.  Thus, if the user wants
+to add the numbers 1.5 and 3.517, it seemed reasonable to give
+him the result 5.017 without requiring him to unnecessarily
+specify his rather obvious requirements for precision.
+.PP
+On the other hand, multiplication and exponentiation produce
+results with many more digits than their operands and it
+seemed reasonable to give as a minimum the number of decimal
+places in the operands but not to give more than that
+number of digits
+unless the user asked for them by specifying a value for \fBscale\fP.
+Square root can be handled in just the same way as multiplication.
+The operation of division gives arbitrarily many decimal places
+and there is simply no way to guess how many places the user
+wants.
+In this case only, the user must
+specify a \fBscale\fP to get any decimal places at all.
+.PP
+The scale of remainder was chosen to make it possible
+to recreate the dividend from the quotient and remainder.
+This is easy to implement; no digits are thrown away.
+.SH
+References
+.IP [1]
+L. L. Cherry, R. Morris,
+.ft I
+BC \- An Arbitrary Precision Desk-Calculator Language.
+.ft
+.IP [2]
+K. C. Knowlton,
+.ft I
+A Fast Storage Allocator,
+.ft
+Comm. ACM \fB8\fP, pp. 623-625 (Oct. 1965).
diff --git a/share/doc/usd/06.bc/Makefile b/share/doc/usd/06.bc/Makefile
index 12dfedd..b4f340c 100644
--- a/share/doc/usd/06.bc/Makefile
+++ b/share/doc/usd/06.bc/Makefile
@@ -4,6 +4,5 @@
 VOLUME=	usd/06.bc
 SRCS=	bc
 MACROS=	-ms
-SRCDIR=	${.CURDIR}/../../../../usr.bin/bc/USD.doc
 
 .include <bsd.doc.mk>
diff --git a/share/doc/usd/06.bc/bc b/share/doc/usd/06.bc/bc
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@@ -0,0 +1,1241 @@
+.\"	$FreeBSD$
+.\"	$OpenBSD: bc,v 1.9 2004/07/09 10:23:05 jmc Exp $
+.\"
+.\" Copyright (C) Caldera International Inc.  2001-2002.
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code and documentation must retain the above
+.\"    copyright notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed or owned by Caldera
+.\"	International, Inc.
+.\" 4. Neither the name of Caldera International, Inc. nor the names of other
+.\"    contributors may be used to endorse or promote products derived from
+.\"    this software without specific prior written permission.
+.\"
+.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
+.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT,
+.\" INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+.\" POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\"	@(#)bc	6.2 (Berkeley) 4/17/91
+.\"
+.if n \{\
+.po 5n
+.ll 70n
+.\}
+.EH 'USD:6-%''BC \- An Arbitrary Precision Desk-Calculator Language'
+.OH 'BC \- An Arbitrary Precision Desk-Calculator Language''USD:6-%'
+.\".RP
+.TL
+BC \- An Arbitrary Precision Desk-Calculator Language
+.AU
+Lorinda Cherry
+.AU
+Robert Morris
+.AI
+.\" .MH
+.AB
+BC is a language and a compiler for doing arbitrary precision arithmetic
+on the PDP-11 under the
+.UX
+time-sharing
+system.  The output of the compiler is interpreted and executed by
+a collection of routines which can input, output, and do
+arithmetic on indefinitely large integers and on scaled fixed-point
+numbers.
+.PP
+These routines are themselves based on a dynamic storage allocator.
+Overflow does not occur until all available core storage
+is exhausted.
+.PP
+The language has a complete control structure as well as immediate-mode
+operation.  Functions can be defined and saved for later execution.
+.PP
+Two five hundred-digit numbers can be multiplied to give a
+thousand digit result in about ten seconds.
+.PP
+A small collection of library functions is also available,
+including sin, cos, arctan, log, exponential, and Bessel functions of
+integer order.
+.PP
+Some of the uses of this compiler are
+.IP \-
+to do computation with large integers,
+.IP \-
+to do computation accurate to many decimal places,
+.IP \-
+conversion of numbers from one base to another base.
+.AE
+.PP
+.SH
+Introduction
+.PP
+BC is a language and a compiler for doing arbitrary precision
+arithmetic on the
+.UX
+time-sharing system [1].
+The compiler was written to make conveniently available a
+collection of routines (called DC [5]) which are capable of doing
+arithmetic on integers of arbitrary size.  The compiler
+is by no means intended to provide a complete programming
+language.
+It is a minimal language facility.
+.PP
+There is a scaling provision that permits the
+use of decimal point notation.
+Provision is made for input and output in bases other than
+decimal.  Numbers can be converted from decimal to octal by
+simply setting the output base to equal 8.
+.PP
+The actual limit on the number of digits that can
+be handled depends on the amount of storage available on the machine.
+Manipulation of numbers with many hundreds of digits
+is possible even on the smallest versions of
+.UX .
+.PP
+The syntax of BC has been deliberately selected to agree
+substantially with the C language [2].  Those who
+are familiar with C will find few surprises in this language.
+.SH
+Simple Computations with Integers
+.PP
+The simplest kind of statement is an arithmetic expression
+on a line by itself.
+For instance, if you type in the line:
+.DS
+.ft B
+142857 + 285714
+.ft P
+.DE
+the program responds immediately with the line
+.DS
+.ft B
+428571
+.ft P
+.DE
+The operators \-, *, /, %, and ^ can also be used; they
+indicate subtraction, multiplication, division, remaindering, and
+exponentiation, respectively.  Division of integers produces an
+integer result truncated toward zero.
+Division by zero produces an error
+comment.
+.PP
+Any term in an expression may be prefixed by a minus sign to
+indicate that it is to be negated (the `unary' minus sign).
+The expression
+.DS
+.ft B
+7+\-3
+.ft P
+.DE
+is interpreted to mean that \-3 is to be added to 7.
+.PP
+More complex expressions with several operators and with
+parentheses are interpreted just as in
+Fortran, with ^ having the greatest binding
+power, then * and % and /, and finally + and \-.
+Contents of parentheses are evaluated before material
+outside the parentheses.
+Exponentiations are
+performed from right to left and the other operators
+from left to right.
+The two expressions
+.DS
+.ft B
+a^b^c  and  a^(b^c)
+.ft P
+.DE
+are equivalent, as are the two expressions
+.DS
+.ft B
+a*b*c  and  (a*b)*c
+.ft P
+.DE
+BC shares with Fortran and C the undesirable convention that
+.DS
+\fBa/b*c\fP  is equivalent to  \fB(a/b)*c\fP
+.ft P
+.DE
+.PP
+Internal storage registers to hold numbers have single lower-case
+letter names.  The value of an expression can be assigned to
+a register in the usual way.  The statement
+.DS
+.ft B
+x = x + 3
+.ft P
+.DE
+has the effect of increasing by three the value of the contents of the
+register named x.
+When, as in this case, the outermost operator is an =, the
+assignment is performed but the result is not printed.
+Only 26 of these named storage registers are available.
+.PP
+There is a built-in square root function whose
+result is truncated to an integer (but see scaling below).
+The lines
+.DS
+.ft B
+x = sqrt(191)
+x
+.ft P
+.DE
+produce the printed result
+.DS
+.ft B
+13
+.ft P
+.DE
+.SH
+Bases
+.PP
+There are special internal quantities, called `ibase' and `obase'.
+The contents of `ibase', initially set to 10,
+determines the base used for interpreting numbers read in.
+For example, the lines
+.DS
+.ft B
+ibase = 8
+11
+.ft P
+.DE
+will produce the output line
+.DS
+.ft B
+9
+.ft P
+.DE
+and you are all set up to do octal to decimal conversions.
+Beware, however of trying to change the input base back
+to decimal by typing
+.DS
+.ft B
+ibase = 10
+.ft P
+.DE
+Because the number 10 is interpreted as octal, this statement will
+have no effect.
+For those who deal in hexadecimal notation,
+the characters A\-F are permitted in numbers
+(no matter what base is in effect)
+and are
+interpreted as digits having values 10\-15 respectively.
+The statement
+.DS
+.ft B
+ibase = A
+.ft P
+.DE
+will change you back to decimal input base no matter what the
+current input base is.
+Negative and large positive input bases are
+permitted but useless.
+No mechanism has been provided for the input of arbitrary
+numbers in bases less than 1 and greater than 16.
+.PP
+The contents of `obase', initially set to 10, are used as the base for output
+numbers.  The lines
+.DS
+.ft B
+obase = 16
+1000
+.ft P
+.DE
+will produce the output line
+.DS
+.ft B
+3E8
+.ft P
+.DE
+which is to be interpreted as a 3-digit hexadecimal number.
+Very large output bases are permitted, and they are sometimes useful.
+For example, large numbers can be output in groups of five digits
+by setting `obase' to 100000.
+Strange (i.e. 1, 0, or negative) output bases are
+handled appropriately.
+.PP
+Very large numbers are split across lines with 70 characters per line.
+Lines which are continued end with \\.
+Decimal output conversion is practically instantaneous, but output
+of very large numbers (i.e., more than 100 digits) with other bases
+is rather slow.
+Non-decimal output conversion of
+a one hundred digit number takes about
+three seconds.
+.PP
+It is best to remember that `ibase' and `obase' have no effect
+whatever on the course of internal computation or
+on the evaluation of expressions, but only affect input and
+output conversion, respectively.
+.SH
+Scaling
+.PP
+A third special internal quantity called `scale' is
+used to determine the scale of calculated
+quantities.
+Numbers may have
+up to a specific number of decimal digits after the decimal point.
+This fractional part is retained in further computations.
+We refer to the number of digits after the decimal point of
+a number as its scale.
+The current implementation allows scales to be as large as can be
+represented by a 32-bit unsigned number minus one.
+This is a non-portable extension.
+The original implementation allowed for a maximum scale of 99.
+.PP
+When two scaled numbers are combined by
+means of one of the arithmetic operations, the result
+has a scale determined by the following rules.  For
+addition and subtraction, the scale of the result is the larger
+of the scales of the two operands.  In this case,
+there is never any truncation of the result.
+For multiplications, the scale of the result is never
+less than the maximum of the two scales of the operands,
+never more than the sum of the scales of the operands
+and, subject to those two restrictions,
+the scale of the result is set equal to the contents of the internal
+quantity `scale'.
+The scale of a quotient is the contents of the internal
+quantity `scale'.  The scale of a remainder is
+the sum of the scales of the quotient and the divisor.
+The result of an exponentiation is scaled as if
+the implied multiplications were performed.
+An exponent must be an integer.
+The scale of a square root is set to the maximum of the scale
+of the argument and the contents of `scale'.
+.PP
+All of the internal operations are actually carried out in terms
+of integers, with digits being discarded when necessary.
+In every case where digits are discarded, truncation and
+not rounding is performed.
+.PP
+The contents of
+`scale' must be no greater than
+4294967294 and no less than 0.  It is initially set to 0.
+.PP
+The internal quantities `scale', `ibase', and `obase' can be
+used in expressions just like other variables.
+The line
+.DS
+.ft B
+scale = scale + 1
+.ft P
+.DE
+increases the value of `scale' by one, and the line
+.DS
+.ft B
+scale
+.ft P
+.DE
+causes the current value of `scale' to be printed.
+.PP
+The value of `scale' retains its meaning as a
+number of decimal digits to be retained in internal
+computation even when `ibase' or `obase' are not equal to 10.
+The internal computations (which are still conducted in decimal,
+regardless of the bases) are performed to the specified number
+of decimal digits, never hexadecimal or octal or any
+other kind of digits.
+.SH
+Functions
+.PP
+The name of a function is a single lower-case letter.
+Function names are permitted to collide with simple
+variable names.
+Twenty-six different defined functions are permitted
+in addition to the twenty-six variable names.
+The line
+.DS
+.ft B
+	define a(x){
+.ft P
+.DE
+begins the definition of a function with one argument.
+This line must be followed by one or more statements,
+which make up the body of the function, ending
+with a right brace }.
+Return of control from a function occurs when a return
+statement is executed or when the end of the function is reached.
+The return statement can take either
+of the two forms
+.DS
+.ft B
+return
+return(x)
+.ft P
+.DE
+In the first case, the value of the function is 0, and in
+the second, the value of the expression in parentheses.
+.PP
+Variables used in the function can be declared as automatic
+by a statement of the form
+.DS
+.ft B
+auto x,y,z
+.ft P
+.DE
+There can be only one `auto' statement in a function and it must
+be the first statement in the definition.
+These automatic variables are allocated space and initialized
+to zero on entry to the function and thrown away on return.  The
+values of any variables with the same names outside the function
+are not disturbed.
+Functions may be called recursively and the automatic variables
+at each level of call are protected.
+The parameters named in a function definition are treated in
+the same way as the automatic variables of that function
+with the single exception that they are given a value
+on entry to the function.
+An example of a function definition is
+.DS
+.ft B
+	define a(x,y){
+		auto z
+		z = x*y
+		return(z)
+	}
+.ft P
+.DE
+The value of this function, when called, will be the
+product of its
+two arguments.
+.PP
+A function is called by the appearance of its name
+followed by a string of arguments enclosed in
+parentheses and separated by commas.
+The result
+is unpredictable if the wrong number of arguments is used.
+.PP
+Functions with no arguments are defined and called using
+parentheses with nothing between them: b().
+.PP
+If the function
+.ft I
+a
+.ft
+above has been defined, then the line
+.DS
+.ft B
+a(7,3.14)
+.ft P
+.DE
+would cause the result 21.98 to be printed and the line
+.DS
+.ft B
+x = a(a(3,4),5)
+.ft P
+.DE
+would cause the value of x to become 60.
+.SH
+Subscripted Variables
+.PP
+A single lower-case letter variable name
+followed by an expression in brackets is called a subscripted
+variable (an array element).
+The variable name is called the array name and the expression
+in brackets is called the subscript.
+Only one-dimensional arrays are
+permitted.  The names of arrays are permitted to
+collide with the names of simple variables and function names.
+Any fractional
+part of a subscript is discarded before use.
+Subscripts must be greater than or equal to zero and 
+less than or equal to 2047.
+.PP
+Subscripted variables may be freely used in expressions, in
+function calls, and in return statements.
+.PP
+An array name may be used as an argument to a function,
+or may be declared as automatic in
+a function definition by the use of empty brackets:
+.DS
+.ft B
+f(a[\|])
+define f(a[\|])
+auto a[\|]
+.ft P
+.DE
+When an array name is so used, the whole contents of the array
+are copied for the use of the function, and thrown away on exit
+from the function.
+Array names which refer to whole arrays cannot be used
+in any other contexts.
+.SH
+Control Statements
+.PP
+The `if', the `while', and the `for' statements
+may be used to alter the flow within programs or to cause iteration.
+The range of each of them is a statement or
+a compound statement consisting of a collection of
+statements enclosed in braces.
+They are written in the following way
+.DS
+.ft B
+if(relation) statement
+if(relation) statement else statement
+while(relation) statement
+for(expression1; relation; expression2) statement
+.ft P
+.DE
+or
+.DS
+.ft B
+if(relation) {statements}
+if(relation) {statements} else {statements}
+while(relation) {statements}
+for(expression1; relation; expression2) {statements}
+.ft P
+.DE
+.PP
+A relation in one of the control statements is an expression of the form
+.DS
+.ft B
+x>y
+.ft P
+.DE
+where  two expressions are related by one of the six relational
+operators `<', `>', `<=', `>=', `==', or `!='.
+The relation `=='
+stands for `equal to' and `!=' stands for `not equal to'.
+The meaning of the remaining relational operators is
+clear.
+.PP
+BEWARE of using `=' instead of `==' in a relational.  Unfortunately,
+both of them are legal, so you will not get a diagnostic
+message, but `=' really will not do a comparison.
+.PP
+The `if' statement causes execution of its range
+if and only if the relation is true.
+Then control passes to the next statement in sequence.
+If an `else' branch is present, the statements in this branch are
+executed if the relation is false.
+The `else' keyword is a non-portable extension.
+.PP
+The `while' statement causes execution of its range
+repeatedly as long as the relation
+is true.  The relation is tested before each execution
+of its range and if the relation
+is false, control passes to the next statement beyond the range
+of the while.
+.PP
+The `for' statement begins
+by executing `expression1'.  Then the relation is tested
+and, if true, the statements in the range of the `for' are executed.
+Then `expression2' is executed.  The relation is tested, and so on.
+The typical use of the `for' statement is for a controlled iteration,
+as in the statement
+.DS
+.ft B
+for(i=1; i<=10; i=i+1) i
+.ft P
+.DE
+which will print the integers from 1 to 10.
+Here are some examples of the use of the control statements.
+.DS
+.ft B
+define f(n){
+auto i, x
+x=1
+for(i=1; i<=n; i=i+1) x=x*i
+return(x)
+}
+.ft P
+.DE
+The line
+.DS
+.ft B
+	f(a)
+.ft P
+.DE
+will print
+.ft I
+a
+.ft
+factorial if
+.ft I
+a
+.ft
+is a positive integer.
+Here is the definition of a function which will
+compute values of the binomial coefficient
+(m and n are assumed to be positive integers).
+.DS
+.ft B
+define b(n,m){
+auto x, j
+x=1
+for(j=1; j<=m; j=j+1) x=x*(n\-j+1)/j
+return(x)
+}
+.ft P
+.DE
+The following function computes values of the exponential function
+by summing the appropriate series
+without regard for possible truncation errors:
+.DS
+.ft B
+scale = 20
+define e(x){
+	auto a, b, c, d, n
+	a = 1
+	b = 1
+	c = 1
+	d = 0
+	n = 1
+	while(1==1){
+		a = a*x
+		b = b*n
+		c = c + a/b
+		n = n + 1
+		if(c==d) return(c)
+		d = c
+	}
+}
+.ft P
+.DE
+.SH
+Some Details
+.PP
+There are some language features that every user should know
+about even if he will not use them.
+.PP
+Normally statements are typed one to a line.  It is also permissible
+to type several statements on a line separated by semicolons.
+.PP
+If an assignment statement is parenthesized, it then has
+a value and it can be used anywhere that an expression can.
+For example, the line
+.DS
+.ft B
+(x=y+17)
+.ft P
+.DE
+not only makes the indicated assignment, but also prints the
+resulting value.
+.PP
+Here is an example of a use of the value of an
+assignment statement even when it is not parenthesized.
+.DS
+.ft B
+x = a[i=i+1]
+.ft P
+.DE
+causes a value to be assigned to x and also increments i
+before it is used as a subscript.
+.PP
+The following constructs work in BC in exactly the same manner
+as they do in the C language.  Consult the appendix or the
+C manuals [2] for their exact workings.
+.DS
+.ft B
+.ta 2i
+x=y=z  is the same as	x=(y=z)
+x += y	x = x+y
+x \-= y	x = x\-y
+x *= y	x = x*y
+x /= y	x = x/y
+x %= y	x = x%y
+x ^= y	x = x^y
+x++	(x=x+1)\-1
+x\-\-	(x=x\-1)+1
+++x	x = x+1
+\-\-x	x = x\-1
+.ft P
+.DE
+Even if you don't intend to use the constructs,
+if you type one inadvertently, something correct but unexpected
+may happen.
+.SH
+Three Important Things
+.PP
+1.  To exit a BC program, type `quit'.
+.PP
+2. There is a comment convention identical to that of C and
+of PL/I.  Comments begin with `/*' and end with `*/'.
+As a non-portable extension, comments may also start with a `#' and end with
+a newline.
+The newline is not part of the comment.
+.PP
+3. There is a library of math functions which may be obtained by
+typing at command level
+.DS
+.ft B
+bc \-l
+.ft P
+.DE
+This command will load a set of library functions
+which, at the time of writing, consists of sine (named `s'),
+cosine (`c'), arctangent (`a'), natural logarithm (`l'),
+exponential (`e') and Bessel functions of integer order (`j(n,x)').  Doubtless more functions will be added
+in time.
+The library sets the scale to 20.  You can reset it to something
+else if you like.
+The design of these mathematical library routines
+is discussed elsewhere [3].
+.PP
+If you type
+.DS
+.ft B
+bc file ...
+.ft P
+.DE
+BC will read and execute the named file or files before accepting
+commands from the keyboard.  In this way, you may load your
+favorite programs and function definitions.
+.SH
+Acknowledgement
+.PP
+The compiler is written in YACC [4]; its original
+version  was written by S. C. Johnson.
+.SH
+References
+.IP [1]
+K. Thompson and D. M. Ritchie,
+.ft I
+UNIX Programmer's Manual,
+.ft
+Bell Laboratories,
+1978.
+.IP [2]
+B. W. Kernighan and
+D. M. Ritchie,
+.ft I
+The C Programming Language,
+.ft
+Prentice-Hall, 1978.
+.IP [3]
+R. Morris,
+.ft I
+A Library of Reference Standard Mathematical Subroutines,
+.ft
+Bell Laboratories internal memorandum, 1975.
+.IP [4]
+S. C. Johnson,
+.ft I
+YACC \(em Yet Another Compiler-Compiler.
+.ft
+Bell Laboratories Computing Science Technical Report #32, 1978.
+.IP [5]
+R. Morris and L. L. Cherry,
+.ft I
+DC \- An Interactive Desk Calculator.
+.ft
+.LP
+.bp
+.ft B
+.DS C
+Appendix
+.DE
+.ft
+.NH
+Notation
+.PP
+In the following pages syntactic categories are in \fIitalics\fP;
+literals are in \fBbold\fP; material in brackets [\|] is optional.
+.NH
+Tokens
+.PP
+Tokens consist of keywords, identifiers, constants, operators,
+and separators.
+Token separators may be blanks, tabs or comments.
+Newline characters or semicolons separate statements.
+.NH 2
+Comments
+.PP
+Comments are introduced by the characters /* and terminated by
+*/.
+As a non-portable extension, comments may also start with a # and
+end with a newline.
+The newline is not part of the comment.
+.NH 2
+Identifiers
+.PP
+There are three kinds of identifiers \- ordinary identifiers, array identifiers
+and function identifiers.
+All three types consist of single lower-case letters.
+Array identifiers are followed by square brackets, possibly
+enclosing an expression describing a subscript.
+Arrays are singly dimensioned and may contain up to 2048
+elements.
+Indexing begins at zero so an array may be indexed from 0 to 2047.
+Subscripts are truncated to integers.
+Function identifiers are followed by parentheses, possibly enclosing arguments.
+The three types of identifiers do not conflict;
+a program can have a variable named \fBx\fP,
+an array named \fBx\fP and a function named \fBx\fP, all of which are separate and
+distinct.
+.NH 2
+Keywords
+.PP
+The following are reserved keywords:
+.ft B
+.ta .5i 1.0i
+.nf
+	ibase	if
+	obase	break
+	scale	define
+	sqrt	auto
+	length	return
+	while	quit
+	for	continue
+	else	last
+	print
+.fi
+.ft
+.NH 2
+Constants
+.PP
+Constants consist of arbitrarily long numbers
+with an optional decimal point.
+The hexadecimal digits \fBA\fP\-\fBF\fP are also recognized as digits with
+values 10\-15, respectively.
+.NH 1
+Expressions
+.PP
+The value of an expression is printed unless the main
+operator is an assignment.
+The value printed is assigned to the special variable \fBlast\fP.
+A single dot may be used as a synonym for \fBlast\fP.
+This is a non-portable extension.
+Precedence is the same as the order
+of presentation here, with highest appearing first.
+Left or right associativity, where applicable, is
+discussed with each operator.
+.bp
+.NH 2
+Primitive expressions
+.NH 3
+Named expressions
+.PP
+Named expressions are
+places where values are stored.
+Simply stated,
+named expressions are legal on the left
+side of an assignment.
+The value of a named expression is the value stored in the place named.
+.NH 4
+\fIidentifiers\fR
+.PP
+Simple identifiers are named expressions.
+They have an initial value of zero.
+.NH 4
+\fIarray-name\fP\|[\|\fIexpression\fP\|]
+.PP
+Array elements are named expressions.
+They have an initial value of zero.
+.NH 4
+\fBscale\fR, \fBibase\fR and \fBobase\fR
+.PP
+The internal registers
+\fBscale\fP, \fBibase\fP and \fBobase\fP are all named expressions.
+\fBscale\fP is the number of digits after the decimal point to be
+retained in arithmetic operations.
+\fBscale\fR has an initial value of zero.
+\fBibase\fP and \fBobase\fP are the input and output number
+radix respectively.
+Both \fBibase\fR and \fBobase\fR have initial values of 10.
+.NH 3
+Function calls
+.NH 4
+\fIfunction-name\fB\|(\fR[\fIexpression\fR\|[\fB,\|\fIexpression\|\fR.\|.\|.\|]\|]\fB)
+.PP
+A function call consists of a function name followed by parentheses
+containing a comma-separated list of
+expressions, which are the function arguments.
+A whole array passed as an argument is specified by the
+array name followed by empty square brackets.
+All function arguments are passed by
+value.
+As a result, changes made to the formal parameters have
+no effect on the actual arguments.
+If the function terminates by executing a return
+statement, the value of the function is
+the value of the expression in the parentheses of the return
+statement or is zero if no expression is provided
+or if there is no return statement.
+.NH 4
+sqrt\|(\|\fIexpression\fP\|)
+.PP
+The result is the square root of the expression.
+The result is truncated in the least significant decimal place.
+The scale of the result is
+the scale of the expression or the
+value of
+.ft B
+scale,
+.ft
+whichever is larger.
+.NH 4
+length\|(\|\fIexpression\fP\|)
+.PP
+The result is the total number of significant decimal digits in the expression.
+The scale of the result is zero.
+.NH 4
+scale\|(\|\fIexpression\fP\|)
+.PP
+The result is the scale of the expression.
+The scale of the result is zero.
+.NH 3
+Constants
+.PP
+Constants are primitive expressions.
+.NH 3
+Parentheses
+.PP
+An expression surrounded by parentheses is
+a primitive expression.
+The parentheses are used to alter the
+normal precedence.
+.NH 2
+Unary operators
+.PP
+The unary operators
+bind right to left.
+.NH 3
+\-\|\fIexpression\fP
+.PP
+The result is the negative of the expression.
+.NH 3
+++\|\fInamed-expression\fP
+.PP
+The named expression is
+incremented by one.
+The result is the value of the named expression after
+incrementing.
+.NH 3
+\-\-\|\fInamed-expression\fP
+.PP
+The named expression is
+decremented by one.
+The result is the value of the named expression after
+decrementing.
+.NH 3
+\fInamed-expression\fP\|++
+.PP
+The named expression is
+incremented by one.
+The result is the value of the named expression before
+incrementing.
+.NH 3
+\fInamed-expression\fP\|\-\-
+.PP
+The named expression is
+decremented by one.
+The result is the value of the named expression before
+decrementing.
+.NH 2
+Exponentiation operator
+.PP
+The exponentiation operator binds right to left.
+.NH 3
+\fIexpression\fP ^ \fIexpression\fP
+.PP
+The result is the first
+expression raised to the power of the
+second expression.
+The second expression must be an integer.
+If \fIa\fP
+is the scale of the left expression
+and \fIb\fP is the absolute value
+of the right expression,
+then the scale of the result is:
+.PP
+min\|(\|\fIa\(mub\fP,\|max\|(\|\fBscale\fP,\|\fIa\fP\|)\|)
+.NH 2
+Multiplicative operators
+.PP
+The operators *, /, % bind left to right.
+.NH 3
+\fIexpression\fP * \fIexpression\fP
+.PP
+The result is the product
+of the two expressions.
+If \fIa\fP and \fIb\fP are the
+scales of the two expressions,
+then the scale of the result is:
+.PP
+min\|(\|\fIa+b\fP,\|max\|(\|\fBscale\fP,\|\fIa\fP,\|\fIb\fP\|)\|)
+.NH 3
+\fIexpression\fP / \fIexpression\fP
+.PP
+The result is the quotient of the two expressions.
+The scale of the result is the value of \fBscale\fR.
+.NH 3
+\fIexpression\fP % \fIexpression\fP
+.PP
+The % operator produces the remainder of the division
+of the two expressions.
+More precisely,
+\fIa\fP%\fIb\fP is \fIa\fP\-\fIa\fP/\fIb\fP*\fIb\fP.
+.PP
+The scale of the result is the sum of the scale of
+the divisor and the value of
+.ft B
+scale
+.ft
+.NH 2
+Additive operators
+.PP
+The additive operators bind left to right.
+.NH 3
+\fIexpression\fP + \fIexpression\fP
+.PP
+The result is the sum of the two expressions.
+The scale of the result is
+the maximum of the scales of the expressions.
+.NH 3
+\fIexpression\fP \- \fIexpression\fP
+.PP
+The result is the difference of the two expressions.
+The scale of the result is the
+maximum of the scales of the expressions.
+.NH 2
+assignment operators
+.PP
+The assignment operators bind right to left.
+.NH 3
+\fInamed-expression\fP = \fIexpression\fP
+.PP
+This expression results in assigning the value of the expression
+on the right
+to the named expression on the left.
+.NH 3
+\fInamed-expression\fP += \fIexpression\fP
+.NH 3
+\fInamed-expression\fP \-= \fIexpression\fP
+.NH 3
+\fInamed-expression\fP *= \fIexpression\fP
+.NH 3
+\fInamed-expression\fP /= \fIexpression\fP
+.NH 3
+\fInamed-expression\fP %= \fIexpression\fP
+.NH 3
+\fInamed-expression\fP ^= \fIexpression\fP
+.PP
+The result of the above expressions is equivalent
+to ``named expression = named expression OP expression'',
+where OP is the operator after the = sign.
+.NH 1
+Relations
+.PP
+Unlike all other operators, the relational operators
+are only valid as the object of an \fBif\fP, \fBwhile\fP,
+or inside a \fBfor\fP statement.
+.NH 2
+\fIexpression\fP < \fIexpression\fP
+.NH 2
+\fIexpression\fP > \fIexpression\fP
+.NH 2
+\fIexpression\fP <= \fIexpression\fP
+.NH 2
+\fIexpression\fP >= \fIexpression\fP
+.NH 2
+\fIexpression\fP == \fIexpression\fP
+.NH 2
+\fIexpression\fP != \fIexpression\fP
+.NH 1
+Storage classes
+.PP
+There are only two storage classes in BC, global and automatic
+(local).
+Only identifiers that are to be local to a function need be 
+declared with the \fBauto\fP command.
+The arguments to a function
+are local to the function.
+All other identifiers are assumed to be global
+and available to all functions.
+All identifiers, global and local, have initial values
+of zero.
+Identifiers declared as \fBauto\fP are allocated on entry to the function 
+and released on returning from the function.
+They therefore do not retain values between function calls.
+\fBauto\fP arrays are specified by the array name followed by empty square brackets.
+.PP
+Automatic variables in BC do not work in exactly the same way
+as in either C or PL/I.  On entry to a function, the old values of
+the names that appear as parameters and as automatic
+variables are pushed onto a stack.  
+Until return is made from the function, reference to these
+names refers only to the new values.
+.NH 1
+Statements
+.PP
+Statements must be separated by semicolon or newline.
+Except where altered by control statements, execution
+is sequential.
+.NH 2
+Expression statements
+.PP
+When a statement is an expression, unless
+the main operator is an assignment, the value
+of the expression is printed, followed by a newline character.
+.NH 2
+Compound statements
+.PP
+Statements may be grouped together and used when one statement is expected
+by surrounding them with { }.
+.NH 2
+Quoted string statements
+.PP
+"any string"
+.sp .5
+This statement prints the string inside the quotes.
+.NH 2
+If statements
+.sp .5
+\fBif\|(\|\fIrelation\fB\|)\|\fIstatement\fR
+.PP
+The substatement is executed if the relation is true.
+.NH 2
+If-else statements
+.sp .5
+\fBif\|(\|\fIrelation\fB\|)\|\fIstatement\fB\|else\|\fIstatement\fR
+.PP
+The first substatement is executed if the relation is true, the second
+substatement if the relation is false.
+The \fBif-else\fR statement is a non-portable extension.
+.NH 2
+While statements
+.sp .5
+\fBwhile\|(\|\fIrelation\fB\|)\|\fIstatement\fR
+.PP
+The statement is executed while the relation
+is true.
+The test occurs before each execution of the statement.
+.NH 2
+For statements
+.sp .5
+\fBfor\|(\|\fIexpression\fB; \fIrelation\fB; \fIexpression\fB\|)\|\fIstatement\fR
+.PP
+The \fBfor\fR statement is the same as
+.nf
+.ft I
+	first-expression
+	\fBwhile\|(\fPrelation\|\fB) {\fP
+		statement
+		last-expression
+	}
+.ft R
+.fi
+.PP
+All three expressions may be left out.
+This is a non-portable extension.
+.NH 2
+Break statements
+.sp .5
+\fBbreak\fP
+.PP
+\fBbreak\fP causes termination of a \fBfor\fP or \fBwhile\fP statement.
+.NH 2
+Continue statements
+.sp .5
+\fBcontinue\fP
+.PP
+\fBcontinue\fP causes the next iteration of a \fBfor\fP or \fBwhile\fP
+statement to start, skipping the remainder of the loop.
+For a \fBwhile\fP statement, execution continues with the evaluation
+of the condition.
+For a \fBfor\fP statement, execution continues with evaluation of
+the last-expression.
+The \fBcontinue\fP statement is a non-portable extension.
+.NH 2
+Auto statements
+.sp .5
+\fBauto \fIidentifier\fR\|[\|\fB,\fIidentifier\fR\|]
+.PP
+The \fBauto\fR statement causes the values of the identifiers to be pushed down.
+The identifiers can be ordinary identifiers or array identifiers.
+Array identifiers are specified by following the array name by empty square
+brackets.
+The auto statement must be the first statement
+in a function definition.
+.NH 2
+Define statements
+.sp .5
+.nf
+\fBdefine(\|\fR[\fIparameter\|\fR[\fB\|,\|\fIparameter\|.\|.\|.\|\fR]\|]\|\fB)\|{\fI
+	statements\|\fB}\fR
+.fi
+.PP
+The \fBdefine\fR statement defines a function.
+The parameters may
+be ordinary identifiers or array names.
+Array names must be followed by empty square brackets.
+As a non-portable extension, the opening brace may also appear on the
+next line.
+.NH 2
+Return statements
+.sp .5
+\fBreturn\fP
+.sp .5
+\fBreturn(\fI\|expression\|\fB)\fR
+.PP
+The \fBreturn\fR statement causes termination of a function,
+popping of its auto variables, and
+specifies the result of the function.
+The first form is equivalent to \fBreturn(0)\fR.
+The result of the function is the result of the expression
+in parentheses.
+Leaving out the expression between parentheses is equivalent to
+\fBreturn(0)\fR.
+As a non-portable extension, the parentheses may be left out.
+.NH 2
+Print
+.PP
+The \fBprint\fR statement takes a list of comma-separated expressions.
+Each expression in the list is evaluated and the computed
+value is printed and assigned to the variable `last'.
+No trailing newline is printed.
+The expression may also be a string enclosed in double quotes.
+Within these strings the following escape sequences may be used:
+\ea 
+for bell (alert),
+`\eb'
+for backspace,
+`\ef'
+for formfeed,
+`\en'
+for newline,   
+`\er'
+for carriage return,
+`\et'
+`for tab,
+`\eq'
+for double quote and
+`\e\e'
+for backslash.
+Any other character following a backslash will be ignored.
+Strings will not be assigned to `last'.
+The \fBprint\fR statement is a non-portable extension.
+.NH 2
+Quit
+.PP
+The \fBquit\fR statement stops execution of a BC program and returns
+control to UNIX when it is first encountered.
+Because it is not treated as an executable statement,
+it cannot be used
+in a function definition or in an 
+.ft B
+if, for,
+.ft
+or
+.ft B
+while
+.ft
+statement.
diff --git a/share/doc/usd/07.mail/Makefile b/share/doc/usd/07.mail/Makefile
index d5a6d3c..790aa96 100644
--- a/share/doc/usd/07.mail/Makefile
+++ b/share/doc/usd/07.mail/Makefile
@@ -6,6 +6,5 @@ SRCS=		mail0.nr mail1.nr mail2.nr mail3.nr mail4.nr mail5.nr mail6.nr \
 		mail7.nr mail8.nr mail9.nr maila.nr
 MACROS=		-me
 USE_TBL=
-SRCDIR=		${.CURDIR}/../../../../usr.bin/mail/USD.doc
 
 .include <bsd.doc.mk>
diff --git a/share/doc/usd/07.mail/mail0.nr b/share/doc/usd/07.mail/mail0.nr
new file mode 100644
index 0000000..e569a5f
--- /dev/null
+++ b/share/doc/usd/07.mail/mail0.nr
@@ -0,0 +1,72 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail0.nr	8.1 (Berkeley) 6/8/93
+.\"
+.\" $FreeBSD$
+.\"
+.eh 'USD:7-%''Mail Reference Manual'
+.oh 'Mail Reference Manual''USD:7-%'
+.if n \
+.nr fs .5v
+.\".he 'Mail Reference Manual'\n(mo/\n(dy/\n(yr'%'
+.tp
+.sp 1.0i
+.sz 12
+.rb
+.(l C
+MAIL REFERENCE MANUAL
+.)l
+.sz 10
+.sp 2
+.i
+.(l C
+Kurt Shoens
+.)l
+.r
+.(l C
+Revised by
+.)l
+.(l C
+.i
+Craig Leres\ \c
+.r
+and\ \c
+.i
+Mark Andrews
+.)l
+.r
+.(l C
+Version 5.5
+
+
+.)l
+.pn 2
diff --git a/share/doc/usd/07.mail/mail1.nr b/share/doc/usd/07.mail/mail1.nr
new file mode 100644
index 0000000..50e7883
--- /dev/null
+++ b/share/doc/usd/07.mail/mail1.nr
@@ -0,0 +1,92 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail1.nr	8.1 (Berkeley) 6/8/93
+.\"
+.sh 1 Introduction
+.pp
+.i Mail
+provides a simple and friendly environment for sending and receiving mail.
+It divides incoming mail into
+its constituent messages and allows the user to deal with them
+in any order.  In addition, it provides a set of
+.i ed -\c
+like commands for manipulating messages and sending mail.
+.i Mail
+offers the user simple editing capabilities to ease the composition
+of outgoing messages, as well as providing the ability to define and send
+to names which address groups of users.  Finally,
+.i Mail
+is able to send and receive messages across such networks as the
+ARPANET, UUCP, and Berkeley network.
+.pp
+This document describes how to use the
+.i Mail
+program to send and receive messages.  The reader is not assumed to
+be familiar with other message handling systems, but should be
+familiar with the \s-2UNIX\s0\**
+.(f
+\** \s-1UNIX\s0 is a trademark of Bell Laboratories.
+.)f
+shell, the text editor, and some of the common \s-2UNIX\s0 commands.
+.q "The \s-2UNIX\s0 Programmer's Manual,"
+.q "An Introduction to Csh,"
+and
+.q "Text Editing with Ex and Vi"
+can be consulted for more information on these topics.
+.pp
+Here is how messages are handled:
+the mail system accepts incoming
+.i messages
+for you from other people
+and collects them in a file, called your
+.i "system mailbox" .
+When you login, the system notifies you if there are any messages
+waiting in your system mailbox.  If you are a
+.i csh
+user, you will be notified when new mail arrives if you inform
+the shell of the location of your mailbox.  On version 7 systems,
+your system mailbox is located in the directory /var/mail
+in a file with your login name.  If your login name is
+.q sam,
+then you can make
+.i csh
+notify you of new mail by including the following line in your .cshrc
+file:
+.(l
+set mail=/var/mail/sam
+.)l
+When you read your mail using
+.i Mail ,
+it reads your system mailbox and separates that file into the
+individual messages that have been sent to you.  You can then
+read, reply to, delete, or save these messages.
+Each message is marked with its author and the date they sent it.
diff --git a/share/doc/usd/07.mail/mail2.nr b/share/doc/usd/07.mail/mail2.nr
new file mode 100644
index 0000000..0419859
--- /dev/null
+++ b/share/doc/usd/07.mail/mail2.nr
@@ -0,0 +1,617 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail2.nr	8.1 (Berkeley) 6/8/93
+.\"
+.bp
+.sh 1 "Common usage"
+.pp
+The
+.i Mail
+command has two distinct usages, according to whether one
+wants to send or receive mail.  Sending mail is simple:  to send a
+message to a user whose login name is, say,
+\*(lqroot,\*(rq
+use the shell
+command:
+.(l
+% Mail root
+.)l
+then type your message.  When you reach the end of the message, type
+an EOT (control\-d) at the beginning of a line, which will cause
+.i Mail
+to echo \*(lqEOT\*(rq and return you to the Shell.  When the user you sent mail
+to next logs in, he will receive the message:
+.(l
+You have mail.
+.)l
+to alert him to the existence of your message.
+.pp
+If, while you are composing the message
+you decide that you do not wish to send it after all, you can
+abort the letter with a \s-2RUBOUT\s0.  Typing a single \s-2RUBOUT\s0
+causes
+.i Mail
+to print
+.(l
+(Interrupt -- one more to kill letter)
+.)l
+Typing a second
+\s-2RUBOUT\s0 causes
+.i Mail
+to save your partial letter on the file
+.q dead.letter
+in your home directory and abort the letter.
+Once you have
+sent mail to someone, there is no way to undo the act, so be
+careful.
+.pp
+The message your recipient reads will consist of the message you
+typed, preceded by a line telling who sent the message (your login name)
+and the date and time it
+was sent.
+.pp
+If you want to send the same message to several other people, you can list
+their login names on the command line.
+Thus,
+.(l
+% Mail sam bob john
+Tuition fees are due next Friday.  Don't forget!!
+<Control\-d>
+EOT
+%
+.)l
+will send the reminder to sam, bob, and john.
+.pp
+If, when you log in, you see the message,
+.(l
+You have mail.
+.)l
+you can read the mail by typing simply:
+.(l
+% Mail
+.)l
+.i Mail
+will respond by typing its version number and date and then listing
+the messages you have waiting.  Then it will type a prompt and await
+your command.  The messages are assigned numbers starting with 1 \*- you
+refer to the messages with these numbers.
+.i Mail
+keeps track of which messages are
+.i new
+(have been sent since you last read your mail) and
+.i read
+(have been read by you).  New messages have an
+.b N
+next to them in the header listing and old, but unread messages have
+a
+.b U
+next to them.
+.i Mail
+keeps track of new/old and read/unread messages by putting a
+header field called
+.q Status
+into your messages.
+.pp
+To look at a specific message, use the
+.b type
+command, which may be abbreviated to simply
+.b t .
+For example, if you had the following messages:
+.(l
+N 1 root     Wed Sep 21 09:21  "Tuition fees"
+N 2 sam      Tue Sep 20 22:55
+.)l
+you could examine the first message by giving the command:
+.(l
+type 1
+.)l
+which might cause
+.i Mail
+to respond with, for example:
+.(l
+Message  1:
+From root  Wed Sep 21 09:21:45 1978
+Subject: Tuition fees
+Status: R
+
+Tuition fees are due next Wednesday.  Don't forget!!
+
+.)l
+Many
+.i Mail
+commands that operate on messages take a message number as an
+argument like the
+.b type
+command.  For these commands, there is a notion of a current
+message.  When you enter the
+.i Mail
+program, the current message is initially the first one.  Thus,
+you can often omit the message number and use, for example,
+.(l
+t
+.)l
+to type the current message.  As a further shorthand, you can type a message
+by simply giving its message number.  Hence,
+.(l
+1
+.)l
+would type the first message.
+.pp
+Frequently, it is useful to read the messages in your mailbox in order,
+one after another.  You can read the next message in
+.i Mail
+by simply typing a newline.  As a special case, you can type a newline
+as your first command to
+.i Mail
+to type the first message.
+.pp
+If, after typing a message, you wish to immediately send a reply,
+you can do so with the
+.b reply
+command.
+.b Reply ,
+like
+.b type ,
+takes a message number as an argument.
+.i Mail
+then begins a message addressed to the user who sent you the message.
+You may then type in your letter in reply, followed by a <control-d>
+at the beginning of a line, as before.
+.i Mail
+will type EOT, then type the ampersand prompt to indicate its readiness
+to accept another command.  In our example, if, after typing the
+first message, you wished to reply to it, you might give the command:
+.(l
+reply
+.)l
+.i Mail
+responds by typing:
+.(l
+To: root
+Subject: Re: Tuition fees
+.)l
+and waiting for you to enter your letter.
+You are now in the message collection mode described at the beginning
+of this section and
+.i Mail
+will gather up your message up to a control\-d.
+Note that it copies the subject
+header from the original message.  This is useful in that correspondence
+about a particular matter will tend to retain the same subject heading,
+making it easy to recognize.  If there are other header fields in
+the message, the information found will also be used.
+For example, if the letter had a
+.q "To:"
+header listing several recipients,
+.i Mail
+would arrange to send your replay to the same people as well.
+Similarly, if the original message contained a
+.q "Cc:"
+(carbon copies to) field,
+.i Mail
+would send your reply to
+.i those
+users, too.
+.i Mail
+is careful, though, not too send the message to
+.i you ,
+even if you appear in the
+.q "To:"
+or
+.q "Cc:"
+field, unless you ask to be included explicitly.  See section 4 for more
+details.
+.pp
+After typing in your letter, the dialog with
+.i Mail
+might look like the following:
+.(l
+reply
+To: root
+Subject: Tuition fees
+
+Thanks for the reminder
+EOT
+&
+.)l
+.pp
+The
+.b reply
+command is especially useful for sustaining extended conversations
+over the message system, with other
+.q listening
+users receiving copies of the conversation.  The
+.b reply
+command can be abbreviated to
+.b r .
+.pp
+Sometimes you will receive a message that has been sent to
+several people and wish to reply
+.i only
+to the person who sent it.
+.b Reply
+with a capital
+.b R
+replies to a message, but sends a copy to the sender only.
+.pp
+If you wish, while reading your mail, to send a message to someone,
+but not as a reply to one of your messages, you can send the message
+directly with the
+.b mail
+command, which takes as arguments the names of the recipients you wish
+to send to.  For example, to send a message to
+.q frank,
+you would do:
+.(l
+mail frank
+This is to confirm our meeting next Friday at 4.
+EOT
+&
+.)l
+The
+.b mail
+command can be abbreviated to
+.b m .
+.pp
+Normally, each message you receive is saved in the file
+.i mbox
+in your login directory at the time you leave
+.i Mail .
+Often,
+however, you will not want to save a particular message you
+have received because it is only of passing interest.  To avoid
+saving a message in
+.i mbox
+you can delete it using the
+.b delete
+command.  In our example,
+.(l
+delete 1
+.)l
+will prevent
+.i Mail
+from saving message 1 (from root) in
+.i mbox .
+In addition to not saving deleted messages,
+.i Mail
+will not let
+you type them, either.  The effect is to make the message disappear
+altogether, along with its number.  The
+.b delete
+command can be abbreviated to simply
+.b d .
+.pp
+Many features of
+.i Mail
+can be tailored to your liking with the
+.b set
+command.  The
+.b set
+command has two forms, depending on whether you are setting
+a
+.i binary
+option or a
+.i valued
+option.
+Binary options are either on or off.  For example, the
+.q ask
+option informs
+.i Mail
+that each time you send a message, you want it to prompt you for
+a subject header, to be included in the message.
+To set the
+.q ask
+option, you would type
+.(l
+set ask
+.)l
+.pp
+Another useful
+.i Mail
+option is
+.q hold.
+Unless told otherwise,
+.i Mail
+moves the messages from your system mailbox to the file
+.i mbox
+in your home directory when you leave
+.i Mail .
+If you want
+.i Mail
+to keep your letters in the system mailbox instead, you can set the
+.q hold
+option.
+.pp
+Valued options are values which
+.i Mail
+uses to adapt to your tastes.  For example, the
+.q SHELL
+option tells
+.i Mail
+which shell you like to use, and is specified by
+.(l
+set SHELL=/bin/csh
+.)l
+for example.  Note that no spaces are allowed in
+.q "SHELL=/bin/csh."
+A complete list of the
+.i Mail
+options appears in section 5.
+.pp
+Another important valued option is
+.q crt.
+If you use a fast video terminal, you will find that when you
+print long messages, they fly by too quickly for you to read them.
+With the
+.q crt
+option, you can make
+.i Mail
+print any message larger than a given number of lines by sending
+it through a paging program. This program is specified by the
+valued option \fBPAGER\fP.
+If \fBPAGER\fP is not set, a default paginator is used.
+For example, most CRT users with 24-line screens should do:
+.(l
+set crt=24
+.)l
+to paginate messages that will not fit on their screens.
+In the default state, \fImore\fP (default paginator) prints a screenful of
+information, then types --More--.  Type a space to see the next screenful.
+.pp
+Another adaptation to user needs that
+.i Mail
+provides is that of
+.i aliases .
+An alias is simply a name which stands for one or more
+real user names.
+.i Mail
+sent to an alias is really sent to the list of real users
+associated with it.  For example, an alias can be defined for the
+members of a project, so that you can send mail to the whole project
+by sending mail to just a single name.  The
+.b alias
+command in
+.i Mail
+defines an alias.  Suppose that the users in a project are
+named Sam, Sally, Steve, and Susan.  To define an alias called
+.q project
+for them, you would use the
+.i Mail
+command:
+.(l
+alias project sam sally steve susan
+.)l
+The
+.b alias
+command can also be used to provide a convenient name for someone
+whose user name is inconvenient.  For example, if a user named
+.q "Bob Anderson"
+had the login name
+.q anderson,"
+you might want to use:
+.(l
+alias bob anderson
+.)l
+so that you could send mail to the shorter name,
+.q bob.
+.pp
+While the
+.b alias
+and
+.b set
+commands allow you to customize
+.i Mail ,
+they have the drawback that they must be retyped each time you enter
+.i Mail .
+To make them more convenient to use,
+.i Mail
+always looks for two files when it is invoked.  It first reads
+a system wide file
+.q /etc/mail.rc,
+then a user specific file,
+.q .mailrc,
+which is found in the user's home directory.
+The system wide file
+is maintained by the system administrator and
+contains
+.b set
+commands that are applicable to all users of the system.
+The
+.q .mailrc
+file is usually used by each user to set options the way he likes
+and define individual aliases.
+For example, my .mailrc file looks like this:
+.(l
+set ask nosave SHELL=/bin/csh
+.)l
+As you can see, it is possible to set many options in the
+same
+.b set
+command.  The
+.q nosave
+option is described in section 5.
+.pp
+Mail aliasing is implemented
+at the system-wide level
+by the mail delivery
+system
+.i sendmail .
+These aliases are stored in the file /usr/lib/aliases and are
+accessible to all users of the system.
+The lines in /usr/lib/aliases are of
+the form:
+.(l
+alias: name\*<1\*>, name\*<2\*>, name\*<3\*>
+.)l
+where
+.i alias
+is the mailing list name and the
+.i name\*<i\*>
+are the members of the list.  Long lists can be continued onto the next
+line by starting the next line with a space or tab.  Remember that you
+must execute the shell command
+.i newaliases
+after editing /usr/lib/aliases since the delivery system
+uses an indexed file created by
+.i newaliases .
+.pp
+We have seen that
+.i Mail
+can be invoked with command line arguments which are people
+to send the message to, or with no arguments to read mail.
+Specifying the
+.rb \-f
+flag on the command line causes
+.i Mail
+to read messages from a file other than your system mailbox.
+For example, if you have a collection of messages in
+the file
+.q letters
+you can use
+.i Mail
+to read them with:
+.(l
+% Mail \-f letters
+.)l
+You can use all
+the
+.i Mail
+commands described in this document to examine, modify, or delete
+messages from your
+.q letters
+file, which will be rewritten when you leave
+.i Mail
+with the
+.b quit
+command described below.
+.pp
+Since mail that you read is saved in the file
+.i mbox
+in your home directory by default, you can read
+.i mbox
+in your home directory by using simply
+.(l
+% Mail \-f
+.)l
+.pp
+Normally, messages that you examine using the
+.b type
+command are saved in the file
+.q mbox
+in your home directory if you leave
+.i Mail
+with the
+.b quit
+command described below.
+If you wish to retain a message in your system mailbox
+you can use the
+.b preserve
+command to tell
+.i Mail
+to leave it there.
+The
+.b preserve
+command accepts a list of message numbers, just like
+.b type
+and may be abbreviated to
+.b pre .
+.pp
+Messages in your system mailbox that you do not examine are
+normally retained in your system mailbox automatically.
+If you wish to have such a message saved in
+.i mbox
+without reading it, you may use the
+.b mbox
+command to have them so saved.  For example,
+.(l
+mbox 2
+.)l
+in our example would cause the second message (from sam)
+to be saved in
+.i mbox
+when the
+.b quit
+command is executed.
+.b Mbox
+is also the way to direct messages to your
+.i mbox
+file if you have set the
+.q hold
+option described above.
+.b Mbox
+can be abbreviated to
+.b mb .
+.pp
+When you have perused all the messages of interest, you can leave
+.i Mail
+with the
+.b quit
+command, which saves the messages you have typed but not
+deleted in the file
+.i mbox
+in your login directory.  Deleted messages are discarded irretrievably,
+and messages left untouched are preserved in your system mailbox so
+that you will see them the next time you type:
+.(l
+% Mail
+.)l
+The
+.b quit
+command can be abbreviated to simply
+.b q .
+.pp
+If you wish for some reason to leave
+.i Mail
+quickly without altering either your system mailbox or
+.i mbox ,
+you can type the
+.b x
+command (short for
+.b exit ),
+which will immediately return you to the Shell without changing anything.
+.pp
+If, instead, you want to execute a Shell command without leaving
+.i Mail ,
+you
+can type the command preceded by an exclamation point, just as in the
+text editor.  Thus, for instance:
+.(l
+!date
+.)l
+will print the current date without leaving
+.i Mail .
+.pp
+Finally, the
+.b help
+command is available to print out a brief summary of the
+.i Mail
+commands, using only the single character command abbreviations.
diff --git a/share/doc/usd/07.mail/mail3.nr b/share/doc/usd/07.mail/mail3.nr
new file mode 100644
index 0000000..8b133ef
--- /dev/null
+++ b/share/doc/usd/07.mail/mail3.nr
@@ -0,0 +1,133 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail3.nr	8.1 (Berkeley) 6/8/93
+.\"
+.sh 1 "Maintaining folders"
+.pp
+.i Mail
+includes a simple facility for maintaining groups of messages together
+in folders.  This section describes this facility.
+.pp
+To use the folder facility, you must tell
+.i Mail
+where you wish to keep your folders.  Each folder of messages will
+be a single file.  For convenience, all of your folders are kept in
+a single directory of your choosing.  To tell
+.i Mail
+where your folder directory is, put a line of the form
+.(l
+set folder=letters
+.)l
+in your
+.i .mailrc
+file.  If, as in the example above, your folder directory does not
+begin with a `/,'
+.i Mail
+will assume that your folder directory is to be found starting from
+your home directory.  Thus, if your home directory is
+.b /home/person
+the above example told
+.i Mail
+to find your folder directory in
+.b /home/person/letters .
+.pp
+Anywhere a file name is expected, you can use a folder name, preceded
+with `+.'  For example, to put a message into a folder with the
+.b save
+command, you can use:
+.(l
+save +classwork
+.)l
+to save the current message in the
+.i classwork
+folder.  If the
+.i classwork
+folder does not yet exist, it will be created.  Note that messages
+which are saved with the
+.b save
+command are automatically removed from your system mailbox.
+.pp
+In order to make a copy of a message in a folder without causing
+that message to be removed from your system mailbox, use the
+.b copy
+command, which is identical in all other respects to the
+.b save
+command.  For example,
+.(l
+copy +classwork
+.)l
+copies the current message into the
+.i classwork
+folder and leaves a copy in your system mailbox.
+.pp
+The
+.b folder
+command
+can be used to direct
+.i Mail
+to the contents of a different folder.
+For example,
+.(l
+folder +classwork
+.)l
+directs
+.i Mail
+to read the contents of the
+.i classwork
+folder.  All of the commands that you can use on your system
+mailbox are also applicable to folders, including
+.b type ,
+.b delete ,
+and
+.b reply .
+To inquire which folder you are currently editing, use simply:
+.(l
+folder
+.)l
+.pp
+To list your current set of folders, use the
+.b folders
+command.
+.pp
+To start
+.i Mail
+reading one of your folders, you can use the
+.b \-f
+option described in section 2.  For example:
+.(l
+% Mail \-f +classwork
+.)l
+will cause
+.i Mail
+to read your
+.i classwork
+folder without looking at your system mailbox.
diff --git a/share/doc/usd/07.mail/mail4.nr b/share/doc/usd/07.mail/mail4.nr
new file mode 100644
index 0000000..1a1e046
--- /dev/null
+++ b/share/doc/usd/07.mail/mail4.nr
@@ -0,0 +1,437 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail4.nr	8.1 (Berkeley) 6/8/93
+.\"
+.bp
+.sh 1 "More about sending mail"
+.sh 2 "Tilde escapes"
+.pp
+While typing in a message to be sent to others, it is often
+useful to be able to invoke the text editor on the partial message,
+print the message, execute a shell command, or do some other
+auxiliary function. 
+.i Mail
+provides these capabilities through
+.i "tilde escapes" ,
+which consist of a tilde (~) at the beginning of a line, followed by
+a single character which indicates the function to be performed.  For
+example, to print the text of the message so far, use:
+.(l
+~p
+.)l
+which will print a line of dashes, the recipients of your message, and
+the text of the message so far.
+Since
+.i Mail
+requires two consecutive \s-2RUBOUT\s0's to abort a letter, you
+can use a single \s-2RUBOUT\s0 to abort the output of ~p or any other
+~ escape without killing your letter.
+.pp
+If you are dissatisfied with the message as
+it stands, you can invoke the text editor on it using the escape
+.(l
+~e
+.)l
+which causes the message to be copied into a temporary file and an
+instance of the editor to be spawned.  After modifying the message to
+your satisfaction, write it out and quit the editor. 
+.i Mail
+will respond
+by typing
+.(l
+(continue)
+.)l
+after which you may continue typing text which will be appended to your
+message, or type <control-d> to end the message.
+A standard text editor is provided by
+.i Mail .
+You can override this default by setting the valued option
+.q EDITOR
+to something else.  For example, you might prefer:
+.(l
+set EDITOR=/usr/bin/ex
+.)l
+.pp
+Many systems offer a screen editor as an alternative to the standard
+text editor, such as the
+.i vi
+editor from UC Berkeley.
+To use the screen, or
+.i visual
+editor, on your current message, you can use the escape,
+.(l
+~v
+.)l
+~v works like ~e, except that the screen editor is invoked instead.
+A default screen editor is defined by
+.i Mail .
+If it does not suit you, you can set the valued option
+.q VISUAL
+to the path name of a different editor.
+.pp
+It is often useful to be able to include the contents of some
+file in your message; the escape
+.(l
+~r filename
+.)l
+is provided for this purpose, and causes the named file to be appended
+to your current message. 
+.i Mail
+complains if the file doesn't exist
+or can't be read.  If the read is successful, the number of lines and
+characters appended to your message is printed, after which you may continue
+appending text.  The filename may contain shell metacharacters like * and ?
+which are expanded according to the conventions of your shell.
+.pp
+As a special case of ~r, the escape
+.(l
+~d
+.)l
+reads in the file
+.q dead.letter
+in your home directory.  This is often useful since
+.i Mail
+copies the text
+of your message there when you abort a message with \s-2RUBOUT\s0.
+.pp
+To save the current text of your message on a file you may use the
+.(l
+~w filename
+.)l
+escape. 
+.i Mail
+will print out the number of lines and characters written
+to the file, after which you may continue appending text to your message.
+Shell metacharacters may be used in the filename, as in ~r and are expanded
+with the conventions of your shell.
+.pp
+If you are sending mail from within
+.i Mail's
+command mode
+you can read a message sent to you into the message
+you are constructing with the escape:
+.(l
+~m 4
+.)l
+which will read message 4 into the current message, shifted right by
+one tab stop.  You can name any non-deleted message, or list of messages.
+Messages can also be forwarded without shifting by a tab stop with ~f.
+This is the usual way to forward a message.
+.pp
+If, in the process of composing a message, you decide to add additional
+people to the list of message recipients, you can do so with the escape
+.(l
+~t name1 name2 ...
+.)l
+You may name as few or many additional recipients as you wish.  Note
+that the users originally on the recipient list will still receive
+the message; you cannot remove someone from the recipient
+list with ~t.
+.pp
+If you wish, you can associate a subject with your message by using the
+escape
+.(l
+~s Arbitrary string of text
+.)l
+which replaces any previous subject with
+.q "Arbitrary string of text."
+The subject, if given, is sent near the
+top of the message prefixed with
+.q "Subject:"
+You can see what the message will look like by using ~p.
+.pp
+For political reasons, one occasionally prefers to list certain
+people as recipients of carbon copies of a message rather than
+direct recipients.  The escape
+.(l
+~c name1 name2 ...
+.)l
+adds the named people to the
+.q "Cc:"
+list, similar to ~t.
+Again, you can execute ~p to see what the message will look like.
+.pp
+The escape
+.(l
+~b name1 name2 ...
+.)l
+adds the named people to the
+.q "Cc:"
+list, but does not make the names visible in the
+.q "Cc:"
+line ("blind" carbon copy).
+.pp
+The recipients of the message together constitute the
+.q "To:"
+field, the subject the
+.q "Subject:"
+field, and the carbon copies the
+.q "Cc:"
+field.  If you wish to edit these in ways impossible with the ~t, ~s, ~c
+and ~b escapes, you can use the escape
+.(l
+~h
+.)l
+which prints
+.q "To:"
+followed by the current list of recipients and leaves the cursor
+(or printhead) at the end of the line.  If you type in ordinary
+characters, they are appended to the end of the current list of
+recipients.  You can also use your erase character to erase back into
+the list of recipients, or your kill character to erase them altogether.
+Thus, for example, if your erase and kill characters are the standard
+(on printing terminals) # and @ symbols,
+.(l
+~h
+To: root kurt####bill
+.)l
+would change the initial recipients
+.q "root kurt"
+to
+.q "root bill."
+When you type a newline,
+.i Mail
+advances to the
+.q "Subject:"
+field, where the same rules apply.  Another newline brings you to
+the
+.q "Cc:"
+field, which may be edited in the same fashion.  Another newline
+brings you to the
+.q "Bcc:"
+("blind" carbon copy) field, which follows the same rules as the "Cc:"
+field.  Another newline
+leaves you appending text to the end of your message.  You can use
+~p to print the current text of the header fields and the body
+of the message.
+.pp
+To effect a temporary escape to the shell, the escape
+.(l
+~!command
+.)l
+is used, which executes
+.i command
+and returns you to mailing mode without altering the text of
+your message.  If you wish, instead, to filter the body of your
+message through a shell command, then you can use
+.(l
+~|command
+.)l
+which pipes your message through the command and uses the output
+as the new text of your message.  If the command produces no output,
+.i Mail
+assumes that something is amiss and retains the old version
+of your message.  A frequently-used filter is the command
+.i fmt ,
+designed to format outgoing mail.
+.pp
+To effect a temporary escape to
+.i Mail
+command mode instead, you can use the
+.(l
+~:\fIMail command\fP
+.)l
+escape.  This is especially useful for retyping the message you are
+replying to, using, for example:
+.(l
+~:t
+.)l
+It is also useful for setting options and modifying aliases.
+.pp
+If you wish abort the current message, you can use the escape
+.(l
+~q
+.)l
+This will terminate the current message and return you to the
+shell (or \fIMail\fP if you were using the \fBmail\fP command).
+If the \fBsave\fP option is set, the message will be copied
+to the file
+.q dead.letter
+in your home directory.
+.pp
+If you wish (for some reason) to send a message that contains
+a line beginning with a tilde, you must double it.  Thus, for example,
+.(l
+~~This line begins with a tilde.
+.)l
+sends the line
+.(l
+~This line begins with a tilde.
+.)l
+.pp
+Finally, the escape
+.(l
+~?
+.)l
+prints out a brief summary of the available tilde escapes.
+.pp
+On some terminals (particularly ones with no lower case)
+tilde's are difficult to type.
+.i Mail
+allows you to change the escape character with the
+.q escape
+option.  For example, I set
+.(l
+set escape=]
+.)l
+and use a right bracket instead of a tilde.  If I ever need to
+send a line beginning with right bracket, I double it, just as for ~.
+Changing the escape character removes the special meaning of ~.
+.sh 2 "Network access"
+.pp
+This section describes how to send mail to people on other machines.
+Recall that sending to a plain login name sends mail to that person
+on your machine.  If your machine is directly (or sometimes, even,
+indirectly) connected to the Arpanet, you can send messages to people
+on the Arpanet using a name of the form
+.(l
+name@host.domain
+.)l
+where
+.i name
+is the login name of the person you're trying to reach,
+.i host
+is the name of the machine on the Arpanet,
+and 
+.i domain
+is the higher-level scope within which the hostname is known, e.g. EDU (for educational
+institutions), COM (for commercial entities), GOV (for governmental agencies),
+ARPA for many other things, BITNET or CSNET for those networks.
+.pp
+If your recipient logs in on a machine connected to yours by
+UUCP (the Bell Laboratories supplied network that communicates
+over telephone lines), sending mail can be a bit more complicated.
+You must know the list of machines through which your message must
+travel to arrive at his site.  So, if his machine is directly connected
+to yours, you can send mail to him using the syntax:
+.(l
+host!name
+.)l
+where, again,
+.i host
+is the name of the machine and
+.i name
+is the login name.
+If your message must go through an intermediary machine first, you
+must use the syntax:
+.(l
+intermediary!host!name
+.)l
+and so on.  It is actually a feature of UUCP that the map of all
+the systems in the network is not known anywhere (except where people
+decide to write it down for convenience).  Talk to your system administrator
+about good ways to get places; the
+.i uuname
+command will tell you systems whose names are recognized, but not which
+ones are frequently called or well-connected.
+.pp
+When you use the
+.b reply
+command to respond to a letter, there is a problem of figuring out the
+names of the users in the
+.q "To:"
+and
+.q "Cc:"
+lists
+.i "relative to the current machine" .
+If the original letter was sent to you by someone on the local machine,
+then this problem does not exist, but if the message came from a remote
+machine, the problem must be dealt with.
+.i Mail
+uses a heuristic to build the correct name for each user relative
+to the local machine.  So, when you
+.b reply
+to remote mail, the names in the
+.q "To:"
+and
+.q "Cc:"
+lists may change somewhat.
+.sh 2 "Special recipients"
+.pp
+As described previously, you can send mail to either user names or
+.b alias
+names.  It is also possible to send messages directly to files or to
+programs, using special conventions.  If a recipient name has a
+`/' in it or begins with a `+', it is assumed to be the
+path name of a file into which
+to send the message.  If the file already exists, the message is
+appended to the end of the file.  If you want to name a file in
+your current directory (ie, one for which a `/' would not usually
+be needed) you can precede the name with `./'
+So, to send mail to the file
+.q memo
+in the current directory, you can give the command:
+.(l
+% Mail ./memo
+.)l
+If the name begins with a `+,' it is expanded into the full path name
+of the folder name in your folder directory.
+This ability to send mail to files can be used for a variety of
+purposes, such as maintaining a journal and keeping a record of
+mail sent to a certain group of users.  The second example can be
+done automatically by including the full pathname of the record
+file in the
+.b alias
+command for the group.  Using our previous
+.b alias
+example, you might give the command:
+.(l
+alias project sam sally steve susan /usr/project/mail_record
+.)l
+Then, all mail sent to "project" would be saved on the file
+.q /usr/project/mail_record
+as well as being sent to the members of the project.  This file
+can be examined using
+.i "Mail \-f" .
+.pp
+It is sometimes useful to send mail directly to a program, for
+example one might write a project billboard program and want to access
+it using
+.i Mail .
+To send messages to the billboard program, one can send mail
+to the special name `|billboard' for example.
+.i Mail
+treats recipient names that begin with a `|' as a program to send
+the mail to.  An
+.b alias
+can be set up to reference a `|' prefaced name if desired.
+.i Caveats :
+the shell treats `|' specially, so it must be quoted on the command
+line.  Also, the `| program' must be presented as a single argument to
+mail.  The safest course is to surround the entire name with double
+quotes.  This also applies to usage in the
+.b alias
+command.  For example, if we wanted to alias `rmsgs' to `rmsgs \-s'
+we would need to say:
+.(l
+alias rmsgs "| rmsgs -s"
+.)l
diff --git a/share/doc/usd/07.mail/mail5.nr b/share/doc/usd/07.mail/mail5.nr
new file mode 100644
index 0000000..10e707c
--- /dev/null
+++ b/share/doc/usd/07.mail/mail5.nr
@@ -0,0 +1,1042 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail5.nr	8.1 (Berkeley) 6/8/93
+.\" $FreeBSD$
+.\"
+.bp
+.sh 1 "Additional features"
+.pp
+This section describes some additional commands useful for
+reading your mail, setting options, and handling lists of messages.
+.sh 2 "Message lists"
+.pp
+Several
+.i Mail
+commands accept a list of messages as an argument.
+Along with
+.b type
+and
+.b delete ,
+described in section 2,
+there is the
+.b from
+command, which prints the message headers associated with the
+message list passed to it.
+The
+.b from
+command is particularly useful in conjunction with some of the
+message list features described below.
+.pp
+A
+.i "message list"
+consists of a list of message numbers, ranges, and names,
+separated by spaces or tabs.  Message numbers may be either
+decimal numbers, which directly specify messages, or one of the
+special characters
+.q \(ua
+.q "."
+or
+.q "$"
+to specify the first relevant, current, or last
+relevant message, respectively.
+.i Relevant
+here means, for most commands
+.q "not deleted"
+and
+.q "deleted"
+for the
+.b undelete
+command.
+.pp
+A range of messages consists of two message numbers (of the form
+described in the previous paragraph) separated by a dash.
+Thus, to print the first four messages, use
+.(l
+type 1\-4
+.)l
+and to print all the messages from the current message to the last
+message, use
+.(l
+type .\-$
+.)l
+.pp
+A
+.i name
+is a user name.  The user names given in the message list are
+collected together and each message selected by other means
+is checked to make sure it was sent by one of the named users.
+If the message consists entirely of user names, then every
+message sent by one of those users that is
+.i relevant
+(in the sense described earlier)
+is selected.  Thus, to print every message sent to you by
+.q root,
+do
+.(l
+type root
+.)l
+.pp
+As a shorthand notation, you can specify simply
+.q *
+to get every
+.i relevant
+(same sense)
+message.  Thus,
+.(l
+type *
+.)l
+prints all undeleted messages,
+.(l
+delete *
+.)l
+deletes all undeleted messages, and
+.(l
+undelete *
+.)l
+undeletes all deleted messages.
+.pp
+You can search for the presence of a word in subject lines with
+.b / .
+For example, to print the headers of all messages that contain the
+word
+.q PASCAL,
+do:
+.(l
+from /pascal
+.)l
+Note that subject searching ignores upper/lower case differences.
+.sh 2 "List of commands"
+.pp
+This section describes all the
+.i Mail
+commands available when
+receiving mail.
+.ip "\fB\-\fP\ \ "
+The
+.rb \-
+command goes to the previous message and prints it.  The
+.rb \-
+command may be given a decimal number
+.i n
+as an argument, in which case the
+.i n th
+previous message is gone to and printed.
+.ip "\fB?\fP\ \ "
+Prints a brief summary of commands.
+.ip "\fB!\fP\ \ "
+Used to preface a command to be executed by the shell.
+.ip "\fBPrint\fP\ \ "
+Like
+.b print ,
+but also print out ignored header fields.  See also
+\fBprint\fP, \fBignore\fP and \fBretain\fP.
+\fBPrint\fP can be abbreviated to \fBP\fP.
+.ip "\fBReply\fP or \fBRespond\fP\ \ "
+Note the capital \fBR\fP in the name.
+Frame a reply to a one or more messages.
+The reply (or replies if you are using this on multiple messages)
+will be sent ONLY to the person who sent you the message
+(respectively, the set of people who sent the messages you are
+replying to).
+You can
+add people using the \fB~t\fP, \fB~c\fP and \fB~b\fP
+tilde escapes.  The subject in your reply is formed by prefacing the
+subject in the original message with
+.q "Re:"
+unless it already began thus.
+If the original message included a
+.q "reply-to"
+header field, the reply will go
+.i only
+to the recipient named by
+.q "reply-to."
+You type in your message using the same conventions available to you
+through the
+.b mail
+command.
+The
+.b Reply
+command is especially useful for replying to messages that were sent
+to enormous distribution groups when you really just want to
+send a message to the originator.  Use it often.
+\fBReply\fP (and \fBRespond\fP) can be abbreviated to \fBR\fP.
+.ip "\fBType\fP\ \ "
+Identical to the
+.b Print
+command.
+\fBType\fP can be abbreviated to \fBT\fP.
+.ip "\fBalias\fP\ \ "
+Define a name to stand for a set of other names.
+This is used when you want to send messages to a certain
+group of people and want to avoid retyping their names.
+For example
+.(l
+alias project john sue willie kathryn
+.)l
+creates an alias
+.i project
+which expands to the four people John, Sue, Willie, and Kathryn.
+If no arguments are given, all currently-defined aliases are printed.
+If one argument is given, that alias is printed (if it exists).
+\fBAlias\fP can be abbreviated to \fBa\fP.
+.ip "\fBalternates\fP\ \ "
+If you have accounts on several machines, you may find it convenient
+to use the /usr/lib/aliases on all the machines except one to direct
+your mail to a single account.
+The
+.b alternates
+command is used to inform
+.i Mail
+that each of these other addresses is really
+.i you .
+.i Alternates
+takes a list of user names and remembers that they are all actually you.
+When you
+.b reply
+to messages that were sent to one of these alternate names,
+.i Mail
+will not bother to send a copy of the message to this other address (which
+would simply be directed back to you by the alias mechanism).
+If
+.i alternates
+is given no argument, it lists the current set of alternate names.
+.b Alternates
+is usually used in the .mailrc file.
+\fBAlternates\fP can be abbreviated to \fBalt\fP.
+.ip "\fBchdir\fP\ \ "
+The
+.b chdir
+command allows you to change your current directory.
+.b Chdir
+takes a single argument, which is taken to be the pathname of
+the directory to change to.  If no argument is given,
+.b chdir
+changes to your home directory.
+\fBChdir\fP can be abbreviated to \fBc\fP.
+.ip "\fBcopy\fP\ \ "
+The
+.b copy
+command does the same thing that
+.b save
+does, except that it does not mark the messages it is used on
+for deletion when you quit.
+\fBCopy\fP can be abbreviated to \fBco\fP.
+.ip "\fBdelete\fP\ \ "
+Deletes a list of messages.  Deleted messages can be reclaimed
+with the
+.b undelete
+command.
+\fBDelete\fP can be abbreviated to \fBd\fP.
+.ip "\fBdp\fP or \fBdt\fP\ \ "
+These
+commands delete the current message and print the next message.
+They are useful for quickly reading and disposing of mail.
+If there is no next message, \fImail\fP says ``at EOF.''
+.ip "\fBedit\fP\ \ "
+To edit individual messages using the text editor, the
+.b edit
+command is provided.  The
+.b edit
+command takes a list of messages as described under the
+.b type
+command and processes each by writing it into the file
+Message\c
+.i x
+where
+.i x
+is the message number being edited and executing the text editor on it.
+When you have edited the message to your satisfaction, write the message
+out and quit, upon which
+.i Mail
+will read the message back and remove the file.
+.b Edit
+can be abbreviated to
+.b e .
+.ip "\fBelse\fP\ \ "
+Marks the end of the then-part of an
+.b if
+statement and the beginning of the
+part to take effect if the condition of the
+.b if
+statement is false.
+.ip "\fBendif\fP\ \ "
+Marks the end of an
+.b if
+statement.
+.ip "\fBexit\fP or \fBxit\fP\ \ "
+Leave
+.i Mail
+without updating the system mailbox or the file your were reading.
+Thus, if you accidentally delete several messages, you can use
+.b exit
+to avoid scrambling your mailbox.
+\fBExit\fP can be abbreviated to \fBex\fP or \fBx\fP.
+.ip "\fBfile\fP\ \ "
+The same as
+.b folder .
+\fBFile\fP can be abbreviated to \fBfi\fP.
+.ip "\fBfolders\fP\ \ "
+List the names of the folders in your folder directory.
+.ip "\fBfolder\fP\ \ "
+The
+.b folder
+command switches to a new mail file or folder.  With no arguments, it
+tells you which file you are currently reading.  If you give
+it an argument, it will write out changes (such as deletions)
+you have made in the current file and read the new file.
+Some special conventions are recognized for the name:
+.(b
+.TS
+center;
+c c
+l a.
+Name	Meaning
+_
+#	Previous file read
+%	Your system mailbox
+%name	\fIName\fP's system mailbox
+&	Your ~/mbox file
++folder	A file in your folder directory
+.TE
+.)b
+\fBFolder\fP can be abbreviated to \fBfo\fP.
+.ip "\fBfrom\fP\ \ "
+The
+.b from
+command takes a list of messages and prints out the header lines for each one;
+hence
+.(l
+from joe
+.)l
+is the easy way to display all the message headers from \*(lqjoe.\*(rq
+\fBFrom\fP can be abbreviated to \fBf\fP.
+.ip "\fBheaders\fP\ \ "
+When you start up
+.i Mail
+to read your mail, it lists the message headers that you have.
+These headers tell you who each message is from, when they were
+received, how many lines and characters each message is, and the
+.q "Subject:"
+header field of each message, if present.  In addition,
+.i Mail
+tags the message header of each message that has been the object
+of the
+.b preserve
+command with a
+.q P.
+Messages that have been
+.b saved
+or
+.b written
+are flagged with a
+.q *.
+Finally,
+.b deleted
+messages are not printed at all.  If you wish to reprint the current
+list of message headers, you can do so with the
+.b headers
+command.  The
+.b headers
+command (and thus the initial header listing)
+only lists the first so many message headers.
+The number of headers listed depends on the speed of your
+terminal.
+This can be overridden by specifying the number of headers you
+want with the
+.i window
+option.
+.i Mail
+maintains a notion of the current
+.q window
+into your messages for the purposes of printing headers.
+Use the
+.b z
+command to move forward and back a window.
+You can move
+.i Mail's
+notion of the current window directly to a particular message by
+using, for example,
+.(l
+headers 40
+.)l
+to move
+.i Mail's
+attention to the messages around message 40.
+If a ``+'' argument is given, then the next screenful of message headers is
+printed, and if a ``\-'' argument is given, the previous screenful of message
+headers is printed.
+\fBHeaders\fP can be abbreviated to \fBh\fP.
+.ip "\fBhelp\fP\ \ "
+Print a brief and usually out of date help message about the commands
+in
+.i Mail .
+The 
+.i man
+page for 
+.i mail
+is usually more up-to-date than either the help message or this manual.
+It is also a synonym for \fB?\fP.
+.ip "\fBhold\fP\ \ "
+Arrange to hold a list of messages in the system mailbox, instead
+of moving them to the file
+.i mbox
+in your home directory.  If you set the binary option
+.i hold ,
+this will happen by default.
+It does not override the \fBdelete\fP command.
+\fBHold\fP can be abbreviated to \fBho\fP.
+.ip "\fBif\fP\ \ "
+Commands in your
+.q .mailrc
+file can be executed conditionally depending on whether you are
+sending or receiving mail with the
+.b if
+command.  For example, you can do:
+.(l
+if receive
+	\fIcommands\fP...
+endif
+.)l
+An
+.b else
+form is also available:
+.(l
+if send
+	\fIcommands\fP...
+else
+	\fIcommands\fP...
+endif
+.)l
+Note that the only allowed conditions are
+.b receive
+and
+.b send .
+.ip "\fBignore\fP \ \ "
+.b N.B.:
+.i Ignore
+has been superseded by
+.i retain.
+.br
+Add the list of header fields named to the
+.i "ignore list" .
+Header fields in the ignore list are not printed on your
+terminal when you print a message.  This allows you to suppress
+printing of certain machine-generated header fields, such as
+.i Via
+which are not usually of interest.  The
+.b Type
+and
+.b Print
+commands can be used to print a message in its entirety, including
+ignored fields.
+If
+.b ignore
+is executed with no arguments, it lists the current set of ignored fields.
+.ip "\fBlist\fP\ \ "
+List the valid
+.i Mail
+commands.
+\fBList\fP can be abbreviated to \fBl\fP.
+.\".ip \fBlocal\fP
+.\"Define a list of local names for this host. This command is useful
+.\"when the host is known by more than one name. Names in the list
+.\"may be qualified be the domain of the host. The first name on the local
+.\"list is the
+.\".i distinguished
+.\"name of the host.
+.\"The names on the local list are used by
+.\".i Mail
+.\"to decide which addresses are local to the host.
+.\"For example:
+.\".(l
+.\"local ucbarpa.BERKELEY.ARPA arpa.BERKELEY.ARPA \\
+.\"	arpavax.BERKELEY.ARPA r.BERKELEY.ARPA \\
+.\"	ucb-arpa.ARPA
+.\".)l
+.\"From this list we see that
+.\".i "fred@ucbarpa.BERKELEY.ARPA",
+.\".i "harold@arpa.BERKELEY",
+.\"and
+.\".i "larry@r"
+.\"are all addresses of users on the local host.
+.\"The
+.\".b local
+.\"command is usually not used be general users since it is designed for
+.\"local configuration; it is usually found in the file /etc/mail.rc.
+.ip "\fBmail\fP\ \ "
+Send mail to one or more people.  If you have the
+.i ask
+option set,
+.i Mail
+will prompt you for a subject to your message.  Then you
+can type in your message, using tilde escapes as described in
+section 4 to edit, print, or modify your message.  To signal your
+satisfaction with the message and send it, type control-d at the
+beginning of a line, or a . alone on a line if you set the option
+.i dot .
+To abort the message, type two interrupt characters (\s-2RUBOUT\s0
+by default) in a row or use the
+.b ~q
+escape.
+The \fBmail\fP command can be abbreviated to \fBm\fP.
+.ip "\fBmbox\fP\ \ "
+Indicate that a list of messages be sent to
+.i mbox
+in your home directory when you quit.  This is the default
+action for messages if you do
+.i not
+have the
+.i hold
+option set.
+.ip "\fBnext\fP or \fB+\fP\ \ "
+The
+.b next
+command goes to the next message and types it.  If given a message list,
+.b next
+goes to the first such message and types it.  Thus,
+.(l
+next root
+.)l
+goes to the next message sent by
+.q root
+and types it.  The
+.b next
+command can be abbreviated to simply a newline, which means that one
+can go to and type a message by simply giving its message number or
+one of the magic characters
+.q "^"
+.q "."
+or
+.q "$".
+Thus,
+.(l
+\&.
+.)l
+prints the current message and
+.(l
+4
+.)l
+prints message 4, as described previously.
+\fBNext\fP can be abbreviated to \fBn\fP.
+.ip "\fBpreserve\fP\ \ "
+Same as
+.b hold .
+Cause a list of messages to be held in your system mailbox when you quit.
+\fBPreserve\fP can be abbreviated to \fBpre\fP.
+.ip "\fBprint\fP\ \ "
+Print the specified messages. If the
+.b crt
+variable is set, messages longer than the number of lines it indicates
+are paged through the command specified by the \fBPAGER\fP variable.
+The \fBprint\fP command can be abbreviated to \fBp\fP.
+.ip "\fBquit\fP\ \ "
+Terminates the session, saving all undeleted, unsaved and unwritten messages 
+in the user's \fImbox\fP file in their login directory
+(messages marked as having been read), preserving all
+messages marked with \fBhold\fP or \fBpreserve\fP or never referenced
+in their system mailbox.
+Any messages that were deleted, saved, written or saved to \fImbox\fP are
+removed from their system mailbox.
+If new mail has arrived during the session, the message
+``You have new mail'' is given.  If given while editing a mailbox file
+with the \fB\-f\fP flag, then the edit file is rewritten.
+A return to the Shell is effected, unless the rewrite of edit file fails,
+in which case the user can escape with the \fBexit\fP command.
+\fBQuit\fP can be abbreviated to \fBq\fP.
+.ip "\fBreply\fP or \fBrespond\fP\ \ "
+Frame a reply to a single message.
+The reply will be sent to the
+person who sent you the message (to which you are replying), plus all
+the people who received the original message, except you.  You can
+add people using the \fB~t\fP, \fB~c\fP and \fB~b\fP
+tilde escapes.  The subject in your reply is formed by prefacing the
+subject in the original message with
+.q "Re:"
+unless it already began thus.
+If the original message included a
+.q "reply-to"
+header field, the reply will go
+.i only
+to the recipient named by
+.q "reply-to."
+You type in your message using the same conventions available to you
+through the
+.b mail
+command.
+The \fBreply\fP (and \fBrespond\fP) command can be abbreviated to \fBr\fP.
+.ip "\fBretain\fP\ \ "
+Add the list of header fields named to the \fIretained list\fP.
+Only the header fields in the retain list
+are shown on your terminal when you print a message.
+All other header fields are suppressed.
+The
+.b Type
+and
+.b Print
+commands can be used to print a message in its entirety.
+If
+.b retain
+is executed with no arguments, it lists the current set of
+retained fields.
+.ip "\fBsave\fP\ \ "
+It is often useful to be able to save messages on related topics
+in a file.  The
+.b save
+command gives you the ability to do this.  The
+.b save
+command takes as an argument a list of message numbers, followed by
+the name of the file in which to save the messages.  The messages
+are appended to the named file, thus allowing one to keep several
+messages in the file, stored in the order they were put there.
+The filename in quotes, followed by the line
+count and character count is echoed on the user's terminal.
+An example of the
+.b save
+command relative to our running example is:
+.(l
+s 1 2 tuitionmail
+.)l
+.b Saved
+messages are not automatically saved in
+.i mbox
+at quit time, nor are they selected by the
+.b next
+command described above, unless explicitly specified.
+\fBSave\fP can be abbreviated to \fBs\fP.
+.ip "\fBset\fP\ \ "
+Set an option or give an option a value.  Used to customize
+.i Mail .
+Section 5.3 contains a list of the options.  Options can be
+.i binary ,
+in which case they are
+.i on
+or
+.i off ,
+or
+.i valued .
+To set a binary option
+.i option
+.i on ,
+do
+.(l
+set option
+.)l
+To give the valued option
+.i option
+the value
+.i value ,
+do
+.(l
+set option=value
+.)l
+There must be no space before or after the ``='' sign.
+If no arguments are given, all variable values are printed.
+Several options can be specified in a single
+.b set
+command.
+\fBSet\fP can be abbreviated to \fBse\fP.
+.ip "\fBshell\fP\ \ "
+The
+.b shell
+command allows you to
+escape to the shell.
+.b Shell
+invokes an interactive shell and allows you to type commands to it.
+When you leave the shell, you will return to
+.i Mail .
+The shell used is a default assumed by
+.i Mail ;
+you can override this default by setting the valued option
+.q SHELL,
+eg:
+.(l
+set SHELL=/bin/csh
+.)l
+\fBShell\fP can be abbreviated to \fBsh\fP.
+.ip "\fBsize\fP\ \ "
+Takes a message list and prints out the size in characters of each
+message.
+.ip "\fBsource\fP\ \ "
+The
+.b source
+command reads
+.i mail
+commands from a file.  It is useful when you are trying to fix your
+.q .mailrc
+file and you need to re-read it.
+\fBSource\fP can be abbreviated to \fBso\fP.
+.ip "\fBtop\fP\ \ "
+The
+.b top
+command takes a message list and prints the first five lines
+of each addressed message.
+If you wish, you can change the number of lines that
+.b top
+prints out by setting the valued option
+.q "toplines."
+On a CRT terminal,
+.(l
+set toplines=10
+.)l
+might be preferred.
+\fBTop\fP can be abbreviated to \fBto\fP.
+.ip "\fBtype\fP\ \ "
+Same as \fBprint\fP.
+Takes a message list and types out each message on the terminal.
+The \fBtype\fP command can be abbreviated to \fBt\fP.
+.ip "\fBundelete\fP \ \"
+Takes a message list and marks each message as \fInot\fP
+being deleted.
+\fBUndelete\fP can be abbreviated to \fBu\fP.
+.ip "\fBunread\fP\ \ "
+Takes a message list and marks each message as
+.i not
+having been read.
+\fBUnread\fP can be abbreviated to \fBU\fP.
+.ip "\fBunset\fP\ \ "
+Takes a list of option names and discards their remembered values;
+the inverse of \fBset\fP .
+.ip "\fBvisual\fP\ \ "
+It is often useful to be able to invoke one of two editors,
+based on the type of terminal one is using.  To invoke
+a display oriented editor, you can use the
+.b visual
+command.  The operation of the
+.b visual
+command is otherwise identical to that of the
+.b edit
+command.
+.ne 2v+\n(psu
+.sp \n(psu
+Both the
+.b edit
+and
+.b visual
+commands assume some default text editors.  These default editors
+can be overridden by the valued options
+.q EDITOR
+and
+.q VISUAL
+for the standard and screen editors.  You might want to do:
+.(l
+set EDITOR=/usr/bin/ex VISUAL=/usr/bin/vi
+.)l
+\fBVisual\fP can be abbreviated to \fBv\fP.
+.ip "\fBwrite\fP\ \ "
+The
+.b save
+command always writes the entire message, including the headers,
+into the file.  If you want to write just the message itself, you
+can use the
+.b write
+command.  The
+.b write
+command has the same syntax as the
+.b save
+command, and can be abbreviated to simply
+.b w .
+Thus, we could write the second message by doing:
+.(l
+w 2 file.c
+.)l
+As suggested by this example, the
+.b write
+command is useful for such tasks as sending and receiving
+source program text over the message system.
+The filename in quotes, followed by the line
+count and character count is echoed on the user's terminal.
+.ip "\fBz\fP\ \ "
+.i Mail
+presents message headers in windowfuls as described under
+the
+.b headers
+command.
+You can move
+.i Mail's
+attention forward to the next window by giving the
+.(l
+z+
+.)l
+command.  Analogously, you can move to the previous window with:
+.(l
+z\-
+.)l
+.sh 2 "Custom options"
+.pp
+Throughout this manual, we have seen examples of binary and valued options.
+This section describes each of the options in alphabetical order, including
+some that you have not seen yet.
+To avoid confusion, please note that the options are either
+all lower case letters or all upper case letters.  When I start a sentence
+such as:
+.q "Ask"
+causes
+.i Mail
+to prompt you for a subject header,
+I am only capitalizing
+.q ask
+as a courtesy to English.
+.ip "\fBEDITOR\fP\ \ "
+The valued option
+.q EDITOR
+defines the pathname of the text editor to be used in the
+.b edit
+command and ~e.  If not defined, a standard editor is used.
+.ip "\fBPAGER\fP\ \ "
+Pathname of the program to use for paginating output when
+it exceeds \fIcrt\fP lines.
+A default paginator is used if this option is not defined.
+.ip "\fBSHELL\fP\ \ "
+The valued option
+.q SHELL
+gives the path name of your shell.  This shell is used for the
+.b !
+command and ~! escape.  In addition, this shell expands
+file names with shell metacharacters like * and ? in them.
+.ip "\fBVISUAL\fP\ \ "
+The valued option
+.q VISUAL
+defines the pathname of the screen editor to be used in the
+.b visual
+command
+and ~v escape.  A standard screen editor is used if you do not define one.
+.ip "\fBappend\fP\ \ "
+The
+.q append
+option is binary and
+causes messages saved in
+.i mbox
+to be appended to the end rather than prepended.
+Normally, \fIMail\fP will put messages in \fImbox\fP
+in the same order that the system puts messages in your system mailbox.
+By setting
+.q append,
+you are requesting that
+.i mbox
+be appended to regardless.  It is in any event quicker to append.
+.ip "\fBask\fP\ \ "
+.q "Ask"
+is a binary option which
+causes
+.i Mail
+to prompt you for the subject of each message you send.
+If you respond with simply a newline, no subject field will be sent.
+.ip "\fBaskcc\fP\ \ "
+.q Askcc
+is a binary option which
+causes you to be prompted for additional carbon copy recipients at the
+end of each message.  Responding with a newline shows your
+satisfaction with the current list.
+.ip "\fBautoprint\fP\ \ "
+.q Autoprint
+is a binary option which
+causes the
+.b delete
+command to behave like
+.b dp
+\*- thus, after deleting a message, the next one will be typed
+automatically.  This is useful when quickly scanning and deleting
+messages in your mailbox.
+.ip "\fBcrt\fP \ \ "
+The valued option
+.q crt
+is used as a threshold to determine how long a message must
+be before
+.b PAGER
+is used to read it.
+.ip "\fBdebug\fP \ \ "
+The binary option
+.q debug
+causes debugging information to be displayed. Use of this
+option is the same as using the \fB\-d\fP command line flag.
+.ip "\fBdot\fP\ \ "
+.q Dot
+is a binary option which, if set, causes
+.i Mail
+to interpret a period alone on a line as the terminator
+of the message you are sending.
+.ip "\fBescape\fP\ \ "
+To allow you to change the escape character used when sending
+mail, you can set the valued option
+.q escape.
+Only the first character of the
+.q escape
+option is used, and it must be doubled if it is to appear as
+the first character of a line of your message.  If you change your escape
+character, then ~ loses all its special meaning, and need no longer be doubled
+at the beginning of a line.
+.ip "\fBfolder\fP\ \ "
+The name of the directory to use for storing folders of messages.
+If this name begins with a `/'
+.i Mail
+considers it to be an absolute pathname; otherwise, the folder directory
+is found relative to your home directory.
+.ip "\fBhold\fP\ \ "
+The binary option
+.q hold
+causes messages that have been read but not manually dealt with
+to be held in the system mailbox. This prevents such messages from
+being automatically swept into your \fImbox\fP file.
+.ip "\fBignore\fP\ \ "
+The binary option
+.q ignore
+causes \s-2RUBOUT\s0 characters from your terminal to be ignored and echoed
+as @'s while you are sending mail.  \s-2RUBOUT\s0 characters retain their
+original meaning in
+.i Mail
+command mode.
+Setting the
+.q ignore
+option is equivalent to supplying the
+.b \-i
+flag on the command line as described in section 6.
+.ip "\fBignoreeof\fP\ \ "
+An option related to
+.q dot
+is
+.q ignoreeof
+which makes
+.i Mail
+refuse to accept a control\-d as the end of a message.
+.q Ignoreeof
+also applies to
+.i Mail
+command mode.
+.ip "\fBkeep\fP\ \ "
+The
+.q keep
+option causes
+.i Mail
+to truncate your system mailbox instead of deleting it when it
+is empty.  This is useful if you elect to protect your mailbox, which
+you would do with the shell command:
+.(l
+chmod 600 /var/mail/yourname
+.)l
+where
+.i yourname
+is your login name.  If you do not do this, anyone can probably read
+your mail, although people usually don't.
+.ip "\fBkeepsave\fP\ \ "
+When you
+.b save
+a message,
+.i Mail
+usually discards it when you
+.b quit .
+To retain all saved messages, set the
+.q keepsave
+option.
+.ip "\fBmetoo\fP\ \ "
+When sending mail to an alias,
+.i Mail
+makes sure that if you are included in the alias, that mail will not
+be sent to you.  This is useful if a single alias is being used by
+all members of the group.  If however, you wish to receive a copy of
+all the messages you send to the alias, you can set the binary option
+.q metoo.
+.ip "\fBnoheader\fP\ \ "
+The binary option
+.q noheader
+suppresses the printing of the version and headers when
+.i Mail
+is first invoked. Setting this option is the same as using
+.b \-N
+on the command line.
+.ip "\fBnosave\fP\ \ "
+Normally,
+when you abort a message with two \s-2RUBOUTs\s0,
+.i Mail
+copies the partial letter to the file
+.q dead.letter
+in your home directory.  Setting the binary option
+.q nosave
+prevents this.
+.ip "\fBReplyall\fP\ \ "
+Reverses the sense of
+.i reply
+and
+.i Reply
+commands.
+.ip "\fBquiet\fP\ \ "
+The binary option
+.q quiet
+suppresses the printing of the version when
+.i Mail
+is first invoked,
+as well as printing the for example
+.q "Message 4:"
+from the
+.b type
+command.
+.ip "\fBrecord\fP\ \ "
+If you love to keep records, then the
+valued option
+.q record
+can be set to the name of a file to save your outgoing mail.
+Each new message you send is appended to the end of the file.
+.ip "\fBscreen\fP\ \ "
+When
+.i Mail
+initially prints the message headers, it determines the number to
+print by looking at the speed of your terminal.  The faster your
+terminal, the more it prints.
+The valued option
+.q screen
+overrides this calculation and
+specifies how many message headers you want printed.
+This number is also used for scrolling with the
+.b z
+command.
+.ip "\fBsendmail\fP\ \ "
+To use an alternate mail delivery system, set the
+.q sendmail
+option to the full pathname of the program to use.  Note:  this is not
+for everyone!  Most people should use the default delivery system.
+.ip "\fBtoplines\fP\ \ "
+The valued option
+.q toplines
+defines the number of lines that the
+.q top
+command will print out instead of the default five lines.
+.ip "\fBverbose\fP\ \ "
+The binary option "verbose" causes
+.i Mail
+to invoke sendmail with the 
+.b \-v
+flag, which causes it to go into verbose mode and announce expansion
+of aliases, etc. Setting the "verbose" option is equivalent to
+invoking
+.i Mail
+with the
+.b \-v
+flag as described in section 6.
diff --git a/share/doc/usd/07.mail/mail6.nr b/share/doc/usd/07.mail/mail6.nr
new file mode 100644
index 0000000..0465a94
--- /dev/null
+++ b/share/doc/usd/07.mail/mail6.nr
@@ -0,0 +1,125 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail6.nr	8.1 (Berkeley) 6/8/93
+.\"
+.bp
+.sh 1 "Command line options"
+.pp
+This section describes command line options for
+.i Mail
+and what they are used for.
+.ip \-N
+Suppress the initial printing of headers.
+.ip \-d
+Turn on debugging information.  Not of general interest.
+.ip "\-f file\ \ "
+Show the messages in
+.i file
+instead of your system mailbox.  If
+.i file
+is omitted,
+.i Mail
+reads
+.i mbox
+in your home directory.
+.ip \-i
+Ignore tty interrupt signals.  Useful on noisy phone lines, which
+generate spurious RUBOUT or DELETE characters.  It's usually
+more effective to change your interrupt character to control\-c,
+for which see the
+.i stty
+shell command.
+.ip \-n
+Inhibit reading of /etc/mail.rc.  Not generally useful, since
+/etc/mail.rc is usually empty.
+.ip "\-s string"
+Used for sending mail.
+.i String
+is used as the subject of the message being composed.  If
+.i string
+contains blanks, you must surround it with quote marks.
+.ip "\-u name"
+Read
+.i names's
+mail instead of your own.  Unwitting others often neglect to protect
+their mailboxes, but discretion is advised. Essentially,
+.b "\-u user"
+is a shorthand way of doing
+.b "\-f /var/mail/user".
+.ip "\-v"
+Use the
+.b \-v
+flag when invoking sendmail. This feature may also be enabled
+by setting the the option "verbose".
+.pp
+The following command line flags are also recognized, but are
+intended for use by programs invoking
+.i Mail
+and not for people.
+.ip "\-T file"
+Arrange to print on
+.i file
+the contents of the
+.i article-id
+fields of all messages that were either read or deleted.
+.b \-T
+is for the
+.i readnews
+program and should NOT be used for reading your mail.
+.ip "\-h number"
+Pass on hop count information.
+.i Mail
+will take the number, increment it, and pass it with
+.b \-h
+to the mail delivery system.
+.b \-h
+only has effect when sending mail and is used for network mail
+forwarding.
+.ip "\-r name"
+Used for network mail forwarding:  interpret
+.i name
+as the sender of the message.  The
+.i name
+and
+.b \-r
+are simply sent along to the mail delivery system.  Also,
+.i Mail
+will wait for the message to be sent and return the exit status.
+Also restricts formatting of message.
+.pp
+Note that
+.b \-h
+and
+.b \-r ,
+which are for network mail forwarding, are not used in practice
+since mail forwarding is now handled separately.  They may
+disappear soon.
diff --git a/share/doc/usd/07.mail/mail7.nr b/share/doc/usd/07.mail/mail7.nr
new file mode 100644
index 0000000..0b2590b
--- /dev/null
+++ b/share/doc/usd/07.mail/mail7.nr
@@ -0,0 +1,107 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail7.nr	8.1 (Berkeley) 6/8/93
+.\"
+.sh 1 "Format of messages"
+.pp
+This section describes the format of messages.
+Messages begin with a
+.i from
+line, which consists of the word
+.q From
+followed by a user name, followed by anything, followed by
+a date in the format returned by the
+.i ctime
+library routine described in section 3 of the Unix Programmer's
+Manual.  A possible
+.i ctime
+format date is:
+.(l
+Tue Dec  1 10:58:23 1981
+.)l
+The
+.i ctime
+date may be optionally followed by a single space and a
+time zone indication, which
+should be three capital letters, such as PDT.
+.pp
+Following the
+.i from
+line are zero or more
+.i "header field"
+lines.
+Each header field line is of the form:
+.(l
+name: information
+.)l
+.i Name
+can be anything, but only certain header fields are recognized as
+having any meaning.  The recognized header fields are:
+.i article-id ,
+.i bcc ,
+.i cc ,
+.i from ,
+.i reply-to ,
+.i sender ,
+.i subject ,
+and
+.i to .
+Other header fields are also significant to other systems; see,
+for example, the current Arpanet message standard for much more
+information on this topic.
+A header field can be continued onto following lines by making the
+first character on the following line a space or tab character.
+.pp
+If any headers are present, they must be followed by a blank line.
+The part that follows is called the
+.i body
+of the message, and must be ASCII text, not containing null characters.
+Each line in the message body must be no longer than 512 characters and
+terminated with an ASCII newline character.
+If binary data must be passed through the mail system, it is suggested
+that this data be encoded in a system which encodes six bits into
+a printable character (i.e.: uuencode).
+For example, one could use the upper and lower case letters, the digits,
+and the characters comma and period to make up the 64 characters.
+Then, one can send a 16-bit binary number
+as three characters.  These characters should be packed into lines,
+preferably lines about 70 characters long as long lines are transmitted
+more efficiently.
+.pp
+The message delivery system always adds a blank line to the end of
+each message.  This blank line must not be deleted.
+.pp
+The UUCP message delivery system sometimes adds a blank line to
+the end of a message each time it is forwarded through a machine.
+.pp
+It should be noted that some network transport protocols enforce
+limits to the lengths of messages.
diff --git a/share/doc/usd/07.mail/mail8.nr b/share/doc/usd/07.mail/mail8.nr
new file mode 100644
index 0000000..b09afbd
--- /dev/null
+++ b/share/doc/usd/07.mail/mail8.nr
@@ -0,0 +1,75 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail8.nr	8.1 (Berkeley) 6/8/93
+.\"
+.bp
+.sh 1 "Glossary"
+.pp
+This section contains the definitions of a few phrases
+peculiar to
+.i Mail .
+.ip "\fIalias\fP"
+An alternative name for a person or list of people.
+.ip "\fIflag\fP"
+An option, given on the command line of
+.i Mail ,
+prefaced with a \-.  For example,
+.b \-f
+is a flag.
+.ip "\fIheader field\fP"
+At the beginning of a message, a line which contains information
+that is part of the structure of the message.  Popular header fields
+include
+.i to ,
+.i cc ,
+and
+.i subject .
+.ip "\fImail\ \ \fP"
+A collection of messages.  Often used in the phrase,
+.q "Have you read your mail?"
+.ip "\fImailbox\fP"
+The place where your mail is stored, typically in the directory
+/var/mail.
+.ip "\fImessage\fP"
+A single letter from someone, initially stored in your
+.i mailbox .
+.ip "\fImessage list\fP"
+A string used in
+.i Mail
+command mode to describe a sequence of messages.
+.ip "\fIoption\fP"
+A piece of special purpose information used to tailor
+.i Mail
+to your taste.
+Options are specified with the
+.b set
+command.
diff --git a/share/doc/usd/07.mail/mail9.nr b/share/doc/usd/07.mail/mail9.nr
new file mode 100644
index 0000000..271548e
--- /dev/null
+++ b/share/doc/usd/07.mail/mail9.nr
@@ -0,0 +1,203 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)mail9.nr	8.1 (Berkeley) 6/8/93
+.\"
+.bp
+.sh 1 "Summary of commands, options, and escapes"
+.pp
+This section gives a quick summary of the
+.i Mail
+commands, binary and valued options, and tilde escapes.
+.pp
+The following table describes the commands:
+.TS
+center ;
+c ci
+lb l.
+Command	Description
+_
++	Same as \fBnext\fP
+-	Back up to previous message
+?	Print brief summary of \fIMail\fP commands
+!	Single command escape to shell
+Print	Type message with ignored fields
+Reply	Reply to author of message only
+Respond	Same as \fBReply\fP
+Type	Type message with ignored fields
+alias	Define an alias as a set of user names
+alternates	List other names you are known by
+chdir	Change working directory, home by default
+copy	Copy a message to a file or folder
+delete	Delete a list of messages
+dp	Same as \fBdt\fP
+dt	Delete current message, type next message
+edit	Edit a list of messages
+else	Start of else part of conditional; see \fBif\fP
+endif	End of conditional statement; see \fBif\fP
+exit	Leave mail without changing anything
+file	Interrogate/change current mail file
+folder	Same as \fBfile\fP
+folders	List the folders in your folder directory
+from	List headers of a list of messages
+headers	List current window of messages
+help	Same as \fB?\fP
+hold	Same as \fBpreserve\fP
+if	Conditional execution of \fIMail\fP commands
+ignore	Set/examine list of ignored header fields
+list	List valid \fIMail\fP commands
+local	List other names for the local host
+mail	Send mail to specified names
+mbox	Arrange to save a list of messages in \fImbox\fP
+next	Go to next message and type it
+preserve	Arrange to leave list of messages in system mailbox
+print	Print messages
+quit	Leave \fIMail\fP; update system mailbox, \fImbox\fP as appropriate
+reply	Compose a reply to a message
+respond	Same as \fBreply\fP
+retain	Supersedes \fBignore\fP
+save	Append messages, headers included, on a file
+set	Set binary or valued options
+shell	Invoke an interactive shell
+size	Prints out size of message list
+source	Read \fImail\fP commands from a file
+top	Print first so many (5 by default) lines of list of messages
+type	Same as \fBprint\fP
+undelete	Undelete list of messages
+unread	Marks list of messages as not been read
+unset	Undo the operation of a \fBset\fP
+visual	Invoke visual editor on a list of messages
+write	Append messages to a file, don't include headers
+xit	Same as \fBexit\fP
+z	Scroll to next/previous screenful of headers
+.TE
+.bp
+.(b
+.pp
+The following table describes the options.  Each option is
+shown as being either a binary or valued option.
+.TS
+center;
+c ci ci
+l ci l.
+Option	Type	Description
+_
+EDITOR	valued	Pathname of editor for ~e and \fBedit\fP
+PAGER	valued	Pathname of paginator for \fBPrint\fP, \fBprint\fP, \fBType\fP and \fBtype\fP
+SHELL	valued	Pathname of shell for \fBshell\fP, ~! and \fB!\fP
+VISUAL	valued	Pathname of screen editor for ~v, \fBvisual\fP
+append	binary	Always append messages to end of \fImbox\fP
+ask	binary	Prompt user for Subject: field when sending
+askcc	binary	Prompt user for additional Cc's at end of message
+autoprint	binary	Print next message after \fBdelete\fP
+crt	valued	Minimum number of lines before using \fBPAGER\fP
+debug	binary	Print out debugging information
+dot	binary	Accept . alone on line to terminate message input
+escape	valued	Escape character to be used instead of\ \ ~
+folder	valued	Directory to store folders in
+hold	binary	Hold messages in system mailbox by default
+ignore	binary	Ignore \s-2RUBOUT\s0 while sending mail
+ignoreeof	binary	Don't terminate letters/command input with \fB\(uaD\fP
+keep	binary	Don't unlink system mailbox when empty
+keepsave	binary	Don't delete \fBsave\fPd messages by default
+metoo	binary	Include sending user in aliases
+noheader	binary	Suppress initial printing of version and headers
+nosave	binary	Don't save partial letter in \fIdead.letter\fP
+quiet	binary	Suppress printing of \fIMail\fP version and message numbers
+record	valued	File to save all outgoing mail in
+screen	valued	Size of window of message headers for \fBz\fP, etc.
+sendmail	valued	Choose alternate mail delivery system
+toplines	valued	Number of lines to print in \fBtop\fP
+verbose	binary	Invoke sendmail with the \fB\-v\fP flag
+.TE
+.)b
+.(b
+.pp
+The following table summarizes the tilde escapes available
+while sending mail.
+.TS
+center;
+c ci ci
+l li l.
+Escape	Arguments	Description
+_
+~!	command	Execute shell command
+~b	name ...	Add names to "blind" Cc: list
+~c	name ...	Add names to Cc: field
+~d		Read \fIdead.letter\fP into message
+~e		Invoke text editor on partial message
+~f	messages	Read named messages
+~h		Edit the header fields
+~m	messages	Read named messages, right shift by tab
+~p		Print message entered so far
+~q		Abort entry of letter; like \s-2RUBOUT\s0
+~r	filename	Read file into message
+~s	string	Set Subject: field to \fIstring\fP
+~t	name ...	Add names to To: field
+~v		Invoke screen editor on message
+~w	filename	Write message on file
+~|	command	Pipe message through \fIcommand\fP
+~:	Mail command	Execute a \fIMail\fP command
+~~	string	Quote a ~ in front of \fIstring\fP
+.TE
+.)b
+.(b
+.pp
+The following table shows the command line flags that
+.i Mail
+accepts:
+.TS
+center;
+c c
+l a.
+Flag	Description
+_
+\-N	Suppress the initial printing of headers
+\-T \fIfile\fP	Article-id's of read/deleted messages to \fIfile\fP
+\-d	Turn on debugging
+\-f \fIfile\fP	Show messages in \fIfile\fP or \fI~/mbox\fP
+\-h \fInumber\fP	Pass on hop count for mail forwarding
+\-i	Ignore tty interrupt signals
+\-n	Inhibit reading of /etc/mail.rc
+\-r \fIname\fP	Pass on \fIname\fP for mail forwarding
+\-s \fIstring\fP	Use \fIstring\fP as subject in outgoing mail
+\-u \fIname\fP	Read \fIname's\fP mail instead of your own
+\-v 	Invoke sendmail with the \fB\-v\fP flag
+.TE
+.)b
+.lp
+Notes:
+.b \-T ,
+.b \-d ,
+.b \-h ,
+and
+.b \-r
+are not for human use.
diff --git a/share/doc/usd/07.mail/maila.nr b/share/doc/usd/07.mail/maila.nr
new file mode 100644
index 0000000..84b01fe
--- /dev/null
+++ b/share/doc/usd/07.mail/maila.nr
@@ -0,0 +1,33 @@
+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)maila.nr	8.1 (Berkeley) 6/8/93
+.\"