Bring in an old faithful tool I've been using for just over 4 years now

(originally on a different OS without mkstemp()), albeit somewhat
bashed and hacked into something that doesn't look too much like
the original any more.  It should be upwardly compatable with
OpenBSD's mktemp(1) but does a couple of extra things.

I've taken OpenBSD's mktemp.1 man page and adapted it to suit.

1 files changed, 182 insertions, 0 deletions

diff --git a/usr.bin/mktemp/mktemp.1 b/usr.bin/mktemp/mktemp.1
new file mode 100644
index 0000000..0ea4ebf
--- /dev/null
+++ b/usr.bin/mktemp/mktemp.1
@@ -0,0 +1,182 @@
+.\" $FreeBSD$
+.\" From: $OpenBSD: mktemp.1,v 1.8 1998/03/19 06:13:37 millert Exp $
+.\"
+.\" Copyright (c) 1989, 1991, 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.
+.\"
+.Dd November, 20, 1996
+.Dt MKTEMP 1
+.Os
+.Sh NAME
+.Nm mktemp
+.Nd make temporary file name (unique)
+.Sh SYNOPSIS
+.Nm mktemp
+.Op Fl d
+.Op Fl q
+.Op Fl t Ar prefix
+.Op Fl u
+.Op Ar template ...
+.Sh DESCRIPTION
+The
+.Nm mktemp
+utility takes each of the given file name templates and overwrites a
+portion of it to create a file name.  This file name is unique
+and suitable for use by the application.  The template may be
+any file name with some number of
+.Ql X Ns s
+appended
+to it, for example
+.Pa /tmp/temp.XXXX .
+The trailing
+.Ql X Ns s
+are replaced with the current process number and/or a
+unique letter combination.
+The number of unique file names
+.Nm
+can return depends on the number of
+.Ql X Ns s
+provided; six
+.Ql X Ns s
+will
+result in
+.Nm
+testing roughly 26 ** 6 combinations.
+.Pp
+If
+.Nm
+can successfully generate a unique file name, the file
+is created with mode 0600 (unless the
+.Fl u
+flag is given) and the filename is printed
+to standard output.
+.Pp
+If the
+.Fl t Ar prefix
+option is given,
+.Nm
+will generate an template string based on the
+.Ar prefix
+and the
+.Ev TMPDIR
+environment variable if set. The default location if
+.Ev TMPDIR
+is not set is
+.Pa /tmp .
+Care should
+be taken to ensure that it is appropriate to use an environment variable
+potentially supplied by the user.
+.Pp
+Any number of temporary files may be created in a single invocation,
+including one based on the internal template resulting from the
+.Fl t
+flag.
+.Pp
+.Nm Mktemp
+is provided to allow shell scripts to safely use temporary files.
+Traditionally, many shell scripts take the name of the program with
+the pid as a suffix and use that as a temporary file name.  This
+kind of naming scheme is predictable and the race condition it creates
+is easy for an attacker to win.  A safer, though still inferior, approach
+is to make a temporary directory using the same naming scheme.  While
+this does allow one to guarantee that a temporary file will not be
+subverted, it still allows a simple denial of service attack.  For these
+reasons it is suggested that
+.Nm
+be used instead.
+.Sh OPTIONS
+.Bl -tag -width indent
+The available options are as follows:
+.It Fl d
+Make a directory instead of a file.
+.It Fl q
+Fail silently if an error occurs.  This is useful if
+a script does not want error output to go to standard error.
+.It Fl t Ar prefix
+Generate a template (using the supplied
+.Ar prefix
+and
+.Ev TMPDIR
+if set) to create a filename template.
+.It Fl u
+Operate in
+.Dq unsafe
+mode.  The temp file will be unlinked before
+.Nm
+exits.  This is slightly better than
+.Fn mktemp 3
+but still introduces a race condition.  Use of this
+option is not encouraged.
+.El
+.Sh RETURN VALUES
+The
+.Nm
+utility
+exits with a value of 0 on success, and 1 on any failure.
+.Sh EXAMPLES
+The following
+.Xr sh 1
+fragment illustrates a simple use of
+.Nm
+where the script should quit if it cannot get a safe
+temporary file.
+.Bd -literal -offset indent
+TMPFILE=`mktemp /tmp/$0.XXXXXX` || exit 1
+echo "program output" >> $TMPFILE
+.Ed
+.Pp
+To allow the use of $TMPDIR:
+.Bd -literal -offset indent
+TMPFILE=`mktemp -t $0` || exit 1
+echo "program output" >> $TMPFILE
+.Ed
+.Pp
+In this case, we want the script to catch the error itself.
+.Bd -literal -offset indent
+TMPFILE=`mktemp -q /tmp/$0.XXXXXX`
+if [ $? -ne 0 ]; then
+	echo "$0: Can't create temp file, exiting..."
+	exit 1
+fi
+.Ed
+.Sh SEE ALSO
+.Xr mktemp 3 ,
+.Xr mkdtemp 3 ,
+.Xr mkstemp 3 ,
+.Xr environ 7
+.Sh HISTORY
+A
+.Nm
+utility appeared in
+.Ox 2.1 .
+This implementation has been written independently based on the man page.
+This man page is taken from OpenBSD.
+.\" Our stupid .Ox macro won't allow me to use .Ox alone.