Improve shell documentation:

* Consistently misspell built-in as builtin.

* Add a builtin(1) manpage and create builtin(1) MLINKS for all shell
  builtin commands for which no standalone utility exists.  These MLINKS
  replace those that were created for csh(1).

* Add appropriate xrefs for builtin(1) to the csh(1) and sh(1) manpages,
  as well as to the manpages of standalone utilities which are supported
  as shell builtin commands in at least one of the shells. In such
  manpages, explain that similar functionality may be provided as a
  shell builtin command.

* Improve sh(1)'s description of the cd builtin command. Csh(1) already
  describes it adequately. Replace the cd(1) manpage with a builtin(1)
  MLINKS link.

* Clean up some mdoc problems: use Xr instead of literal "foo(n)"; use
  Ic instead of Xr for shell builtin commands.

* Undo English contractions.

Reviewed by:	mpp, rgrimes

3 files changed, 287 insertions, 99 deletions

diff --git a/share/man/man1/Makefile b/share/man/man1/Makefile
index 6fc2d4d..6c7e4bc 100644
--- a/share/man/man1/Makefile
+++ b/share/man/man1/Makefile
@@ -1,7 +1,34 @@
 #	@(#)Makefile	8.1 (Berkeley) 6/5/93
 # $FreeBSD$
 
-MAN1=	cd.1 intro.1 wait.1
+MAN1=	builtin.1 intro.1 wait.1
 MLINKS=	intro.1 introduction.1
 
+# Create MLINKS for Shell built in commands for which there are no userland
+# utilities of the same name:
+MLINKS=	builtin.1 alias.1 builtin.1 alloc.1 builtin.1 bg.1 \
+	builtin.1 break.1 builtin.1 breaksw.1 builtin.1 case.1 \
+	builtin.1 cd.1 builtin.1 chdir.1 builtin.1 command.1 \
+	builtin.1 continue.1 builtin.1 cwd.1 builtin.1 do.1 \
+	builtin.1 done.1 builtin.1 default.1 \
+	builtin.1 dirs.1 builtin.1 elif.1 builtin.1 else.1 \
+	builtin.1 end.1 builtin.1 endif.1 builtin.1 endsw.1 \
+	builtin.1 esac.1 builtin.1 eval.1 builtin.1 exec.1 \
+	builtin.1 exit.1 builtin.1 export.1 builtin.1 fc.1 \
+	builtin.1 fg.1 builtin.1 fi.1 builtin.1 for.1 \
+	builtin.1 foreach.1 builtin.1 getopts.1 builtin.1 glob.1 \
+	builtin.1 goto.1 builtin.1 hash.1 builtin.1 hashstat.1 \
+	builtin.1 history.1 builtin.1 if.1 builtin.1 jobid.1 \
+	builtin.1 jobs.1 builtin.1 limit.1 builtin.1 logout.1 \
+	builtin.1 notify.1 builtin.1 onintr.1 builtin.1 popd.1 \
+	builtin.1 pushd.1 builtin.1 readonly.1 builtin.1 rehash.1 \
+	builtin.1 repeat.1 builtin.1 set.1 builtin.1 setenv.1 \
+	builtin.1 setvar.1 builtin.1 shift.1 builtin.1 source.1 \
+	builtin.1 stop.1 builtin.1 suspend.1 builtin.1 switch.1 \
+	builtin.1 then.1 builtin.1 trap.1 builtin.1 type.1 \
+	builtin.1 ulimit.1 builtin.1 umask.1 builtin.1 unalias.1 \
+	builtin.1 unhash.1 builtin.1 unlimit.1 builtin.1 unset.1 \
+	builtin.1 unsetenv.1 builtin.1 until.1 builtin.1 wait.1 \
+	builtin.1 while.1
+
 .include <bsd.prog.mk>
diff --git a/share/man/man1/builtin.1 b/share/man/man1/builtin.1
new file mode 100644
index 0000000..2c60dbd
--- /dev/null
+++ b/share/man/man1/builtin.1
@@ -0,0 +1,259 @@
+.\"
+.\" Copyright (c) 1999 Sheldon Hearn
+.\"
+.\" 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.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+.\"
+.\"	$FreeBSD$
+.\"
+.Dd September 1, 1999
+.Dt BUILTIN 1
+.Os
+.Sh NAME
+.Nm builtin ,
+.Nm alias ,
+.Nm alloc ,
+.Nm bg ,
+.Nm break ,
+.Nm breaksw ,
+.Nm case ,
+.Nm cd ,
+.Nm chdir ,
+.Nm command ,
+.Nm continue ,
+.Nm cwd ,
+.Nm default ,
+.Nm dirs ,
+.Nm do ,
+.Nm done ,
+.Nm echo ,
+.Nm elif ,
+.Nm else ,
+.Nm end ,
+.Nm endif ,
+.Nm endsw ,
+.Nm esac ,
+.Nm eval ,
+.Nm exec ,
+.Nm exit ,
+.Nm export ,
+.Nm fc ,
+.Nm fg ,
+.Nm fi ,
+.Nm for ,
+.Nm foreach ,
+.Nm getopts ,
+.Nm glob ,
+.Nm goto ,
+.Nm hash ,
+.Nm hashstat ,
+.Nm history ,
+.Nm if ,
+.Nm jobid ,
+.Nm jobs ,
+.Nm kill ,
+.Nm limit ,
+.Nm login ,
+.Nm logout ,
+.Nm nice ,
+.Nm nohup ,
+.Nm notify ,
+.Nm onintr ,
+.Nm popd ,
+.Nm printf ,
+.Nm pushd ,
+.Nm pwd ,
+.Nm readonly ,
+.Nm rehash ,
+.Nm repeat ,
+.Nm set ,
+.Nm setenv ,
+.Nm setvar ,
+.Nm shift ,
+.Nm source ,
+.Nm stop ,
+.Nm suspend ,
+.Nm switch ,
+.Nm then ,
+.Nm time ,
+.Nm trap ,
+.Nm type ,
+.Nm ulimit ,
+.Nm umask ,
+.Nm unalias ,
+.Nm unhash ,
+.Nm unlimit ,
+.Nm unset ,
+.Nm unsetenv ,
+.Nm until ,
+.Nm wait ,
+.Nm which ,
+.Nm while
+.Nd shell builtin commands
+.Sh SYNOPSIS
+.Nm builtin
+.Op Fl options
+.Op Ar args ...
+.Sh DESCRIPTION
+Shell builtin commands are commands that can be executed within the
+running shell's process.
+Note that, in the case of
+.Xr csh 1
+builtin commands, the command is executed in a subshell if it occurs as
+any component of a pipeline except the last.
+.Pp
+If a command specified to the shell contains a slash 
+.Dq \&/ ,
+the shell will not execute a builtin command, even if the last component
+of the specified command matches the name of a builtin command. Thus,
+while specifying
+.Dq Ic echo
+causes a builtin command to be executed under shells that support the
+builtin echo command,
+specifying
+.Dq Pa /bin/echo
+or
+.Dq Pa ./echo
+does not.
+.Pp
+While some builtin commands may exist in more than one shell, their
+operation may be different under each shell which supports them.
+Below is a table which lists shell builtin commands, the standard shells
+that support them and whether they exist as standalone utilities.
+.Pp
+Only builtin commands for the
+.Xr csh 1
+and
+.Xr sh 1
+shells are listed here.  Consult the appropriate manual page for
+details on the operation of any given builtin command under those shells.
+Users of other shells will need to consult the documentation supplied
+with the other shells.
+.Bl -column "continueXX" "ExternalXX" "csh(1)" "sh(1)" -offset indent
+.\"
+.\" XXX:
+.\" The correct table header here can not be rendered with mdoc's current
+.\" argument maximum.  When mdoc can handle sufficient arguments, the
+.\" correct table header will be as follows:
+.\" .It Em Command Ta Em External Ta Xr csh 1 Ta Xr sh 1
+.\"
+.It Em Command	External	csh	sh
+.It Ic alias Ta \&No Ta Yes Ta Yes
+.It Ic alloc Ta \&No Ta Yes Ta \&No
+.It Ic bg Ta \&No Ta Yes Ta Yes
+.It Ic break Ta \&No Ta Yes Ta \&No
+.It Ic breaksw Ta \&No Ta Yes Ta \&No
+.It Ic case Ta \&No Ta Yes Ta Yes
+.It Ic cd Ta \&No Ta Yes Ta Yes
+.It Ic chdir Ta \&No Ta Yes Ta \&No
+.It Ic command Ta \&No Ta \&No Ta Yes
+.It Ic continue Ta \&No Ta Yes Ta \&No
+.It Ic cwd Ta \&No Ta Yes Ta \&No
+.It Ic default Ta \&No Ta Yes Ta \&No
+.It Ic dirs Ta \&No Ta Yes Ta \&No
+.It Ic do Ta \&No Ta \&No Ta Yes
+.It Ic done Ta \&No Ta \&No Ta Yes
+.It Ic echo Ta Yes Ta Yes Ta Yes
+.It Ic elif Ta \&No Ta \&No Ta Yes
+.It Ic else Ta \&No Ta Yes Ta \&No
+.It Ic end Ta \&No Ta Yes Ta \&No
+.It Ic endif Ta \&No Ta Yes Ta \&No
+.It Ic endsw Ta \&No Ta Yes Ta \&No
+.It Ic esac Ta \&No Ta \&No Ta Yes
+.It Ic eval Ta \&No Ta Yes Ta Yes
+.It Ic exec Ta \&No Ta Yes Ta Yes
+.It Ic exit Ta \&No Ta Yes Ta Yes
+.It Ic export Ta \&No Ta \&No Ta Yes
+.It Ic fc Ta \&No Ta \&No Ta Yes
+.It Ic fg Ta \&No Ta Yes Ta Yes
+.It Ic fi Ta \&No Ta \&No Ta Yes
+.It Ic for Ta \&No Ta \&No Ta Yes
+.It Ic foreach Ta \&No Ta Yes Ta \&No
+.It Ic getopts Ta \&No Ta \&No Ta Yes
+.It Ic glob Ta \&No Ta Yes Ta \&No
+.It Ic goto Ta \&No Ta Yes Ta \&No
+.It Ic hash Ta \&No Ta \&No Ta Yes
+.It Ic hashstat Ta \&No Ta Yes Ta \&No
+.It Ic history Ta \&No Ta Yes Ta \&No
+.It Ic if Ta \&No Ta Yes Ta \&No
+.It Ic jobid Ta \&No Ta \&No Ta Yes
+.It Ic jobs Ta \&No Ta Yes Ta Yes
+.It Ic kill Ta Yes Ta Yes Ta \&No
+.It Ic limit Ta \&No Ta Yes Ta \&No
+.It Ic login Ta Yes Ta Yes Ta \&No
+.It Ic logout Ta \&No Ta Yes Ta \&No
+.It Ic nice Ta Yes Ta Yes Ta \&No
+.It Ic nohup Ta Yes Ta Yes Ta \&No
+.It Ic notify Ta \&No Ta Yes Ta \&No
+.It Ic onintr Ta \&No Ta Yes Ta \&No
+.It Ic popd Ta \&No Ta Yes Ta \&No
+.It Ic printf Ta Yes Ta Yes Ta Yes
+.It Ic pushd Ta \&No Ta Yes Ta \&No
+.It Ic pwd Ta Yes Ta \&No Ta Yes
+.It Ic readonly Ta \&No Ta \&No Ta Yes
+.It Ic rehash Ta \&No Ta Yes Ta \&No
+.It Ic repeat Ta \&No Ta Yes Ta \&No
+.It Ic set Ta \&No Ta Yes Ta \&No
+.It Ic setenv Ta \&No Ta Yes Ta \&No
+.It Ic setvar Ta \&No Ta \&No Ta Yes
+.It Ic shift Ta \&No Ta Yes Ta Yes
+.It Ic source Ta \&No Ta Yes Ta \&No
+.It Ic stop Ta \&No Ta Yes Ta \&No
+.It Ic suspend Ta \&No Ta Yes Ta \&No
+.It Ic switch Ta \&No Ta Yes Ta \&No
+.It Ic then Ta \&No Ta \&No Ta Yes
+.It Ic time Ta Yes Ta Yes Ta \&No
+.It Ic trap Ta \&No Ta \&No Ta Yes
+.It Ic type Ta \&No Ta \&No Ta Yes
+.It Ic ulimit Ta \&No Ta \&No Ta Yes
+.It Ic umask Ta \&No Ta Yes Ta Yes
+.It Ic unalias Ta \&No Ta Yes Ta Yes
+.It Ic unhash Ta \&No Ta Yes Ta \&No
+.It Ic unlimit Ta \&No Ta Yes Ta \&No
+.It Ic unset Ta \&No Ta Yes Ta Yes
+.It Ic unsetenv Ta \&No Ta Yes Ta \&No
+.It Ic until Ta \&No Ta \&No Ta Yes
+.It Ic wait Ta \&No Ta Yes Ta Yes
+.It Ic which Ta Yes Ta Yes Ta \&No
+.It Ic while Ta \&No Ta Yes Ta \&No
+.El
+.Sh SEE ALSO
+.Xr csh 1 ,
+.Xr echo 1 ,
+.Xr kill 1 ,
+.Xr login 1 ,
+.Xr nice 1 ,
+.Xr nohup 1 ,
+.Xr printf 1 ,
+.Xr pwd 1 ,
+.Xr sh 1 ,
+.Xr time 1 ,
+.Xr which 1
+.Sh HISTORY
+The
+.Nm
+manual page first appeared in
+.Fx 4.0 .
+.Sh AUTHORS
+This manual page was written by
+.An Sheldon Hearn Aq sheldonh@FreeBSD.org .
diff --git a/share/man/man1/cd.1 b/share/man/man1/cd.1
deleted file mode 100644
index 2b812eb..0000000
--- a/share/man/man1/cd.1
+++ /dev/null
@@ -1,98 +0,0 @@
-.\" Copyright (c) 1980, 1990, 1993
-.\"	The Regents of the University of California.  All rights reserved.
-.\"
-.\" This code is derived from software contributed to Berkeley by
-.\" the Institute of Electrical and Electronics Engineers, Inc.
-.\"
-.\" 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.
-.\"
-.\"     @(#)cd.1	8.1 (Berkeley) 6/5/93
-.\" $FreeBSD$
-.\"
-.Dd June 5, 1993
-.Dt CD 1
-.Os BSD 4
-.Sh NAME
-.Nm cd
-.Nd change working directory
-.Sh SYNOPSIS
-.Nm cd
-.Ar directory
-.Sh DESCRIPTION
-.Ar Directory
-is an absolute or relative pathname which becomes the new working
-directory.
-The interpretation of a relative pathname by cd depends on the CDPATH
-environment variable (see below).
-.Sh ENVIRONMENT
-The following environment variables affect the execution of cd:
-.Pp
-.Bl -tag -width indent
-.It Ev CDPATH
-If the
-.Ar directory
-operand does not begin with a slash (/) character, and the first
-component is not dot (.) or dot-dot (..),
-.Nm cd
-searches for the directory relative to each directory named in the
-.Ev CDPATH
-variable, in the order listed.
-The new working directory is set to the first matching directory found.
-An empty string in place of a directory pathname represents the current
-directory.
-If the new working directory was derived from
-.Ev CDPATH ,
-it will be printed to the standard output.
-.It Ev HOME
-If
-.Nm cd
-is invoked without arguments and the
-.Ev HOME
-environment variable exists and contains a directory name, that directory
-becomes the new working directory.
-.El
-.Pp
-See
-.Xr csh 1
-for more information on environment variables.
-.Pp
-The
-.Nm cd
-utility exits 0 on success, and >0 if an error occurs.
-.Sh SEE ALSO
-.Xr csh 1 ,
-.Xr pwd 1 ,
-.Xr sh 1 ,
-.Xr chdir 2
-.Sh STANDARDS
-The
-.Nm cd
-command is expected to be
-.St -p1003.2
-compatible.