Let the pwd program double as realpath(1).

This lets you resolve pathnames to their underlying physical path:

	critter# realpath /sys/kern/subr_disk.c
	/freebsd/src/sys/kern/subr_disk.c

Update the pwd man-page slightly.

4 files changed, 88 insertions, 6 deletions

diff --git a/bin/pwd/Makefile b/bin/pwd/Makefile
index 4a8e66a..be42836 100644
--- a/bin/pwd/Makefile
+++ b/bin/pwd/Makefile
@@ -2,5 +2,7 @@
 # $FreeBSD$
 
 PROG=	pwd
+LINKS=	${BINDIR}/pwd ${BINDIR}/realpath
+MAN1=	pwd.1 realpath.1
 
 .include <bsd.prog.mk>
diff --git a/bin/pwd/pwd.1 b/bin/pwd/pwd.1
index afbe03c..ead40c7 100644
--- a/bin/pwd/pwd.1
+++ b/bin/pwd/pwd.1
@@ -64,6 +64,9 @@ The
 utility is expected to be
 .St -p1003.2
 compatible.
+The
+.Fl L
+flag is not supported.
 .Sh SEE ALSO
 .Xr builtin 1 ,
 .Xr cd 1 ,
diff --git a/bin/pwd/pwd.c b/bin/pwd/pwd.c
index 1adb3c8..849c309 100644
--- a/bin/pwd/pwd.c
+++ b/bin/pwd/pwd.c
@@ -49,6 +49,7 @@ static const char rcsid[] =
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <sys/param.h>
 
 void usage __P((void));
 
@@ -59,13 +60,13 @@ main(argc, argv)
 {
 	int ch;
 	char *p;
+	char buf[MAXPATHLEN];
 
 	/*
 	 * Flags for pwd are a bit strange.  The POSIX 1003.2B/D9 document
 	 * has an optional -P flag for physical, which is what this program
 	 * will produce by default.  The logical flag, -L, should fail, as
-	 * there's no way to display a logical path after forking.  We don't
-	 * document either flag, only adding -P for future portability.
+	 * there's no way to display a logical path after forking.
 	 */
 	while ((ch = getopt(argc, argv, "P")) != -1)
 		switch (ch) {
@@ -78,12 +79,20 @@ main(argc, argv)
 	argc -= optind;
 	argv += optind;
 
-	if (argc != 0)
+	if (argc == 1) {
+		p = realpath(argv[0], buf);
+		if (p == NULL)
+			err(1, argv[0]);
+		(void)printf("%s\n", p);
+	} else  if (argc == 0) {
+		p = getcwd(NULL, 0);
+		if (p == NULL)
+			err(1, ".");
+		(void)printf("%s\n", p);
+	} else {
 		usage();
+	}
 
-	if ((p = getcwd(NULL, 0)) == NULL)
-		err(1, ".");
-	(void)printf("%s\n", p);
 	exit(0);
 }
 
diff --git a/bin/pwd/realpath.1 b/bin/pwd/realpath.1
new file mode 100644
index 0000000..683e152
--- /dev/null
+++ b/bin/pwd/realpath.1
@@ -0,0 +1,68 @@
+.\" Copyright (c) 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.
+.\"
+.\"     @(#)pwd.1	8.2 (Berkeley) 4/28/95
+.\" From: src/bin/pwd/pwd.1,v 1.11 2000/11/20 11:39:39 ru Exp
+.\" $FreeBSD$
+.\"
+.Dd November 24, 2000
+.Dt REALPATH 1
+.Os FreeBSD 5.0
+.Sh NAME
+.Nm realpath
+.Nd return resolved physical path
+.Sh SYNOPSIS
+.Nm
+.Ar path
+.Sh DESCRIPTION
+.Nm realpath
+uses the
+.Xr realpath 3
+function to resolve all symbolic links, extra 
+.Qo
+/
+.Qc
+characters and references to 
+.Pa /./ 
+and 
+.Pa /../
+in
+.Ar path .
+.Pp
+.Sh DIAGNOSTICS
+The
+.Nm
+utility exits 0 on success, and >0 if an error occurs.
+.Sh SEE ALSO
+.Xr realpath 3