1 files changed, 55 insertions, 35 deletions

diff --git a/src/lib/libc/string/strsep.3 b/src/lib/libc/string/strsep.3
index 21aa7376f2..cceeda7577 100644
--- a/src/lib/libc/string/strsep.3
+++ b/src/lib/libc/string/strsep.3
@@ -1,8 +1,11 @@
-.\" Copyright (c) 1990, 1991 The Regents of the University of California.
-.\" All rights reserved.
+.\" $OpenBSD: strsep.3,v 1.12 2007/05/31 19:19:32 jmc Exp $
+.\"
+.\" Copyright (c) 1990, 1991, 1993
+.\"     The Regents of the University of California.  All rights reserved.
 .\"
 .\" This code is derived from software contributed to Berkeley by
 .\" Chris Torek.
+.\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
 .\" are met:
@@ -11,11 +14,7 @@
 .\" 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
+.\" 3. 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.
 .\"
@@ -31,10 +30,9 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     from: @(#)strsep.3      5.3 (Berkeley) 4/19/91
-.\"     $Id: strsep.3,v 1.1.1.1 1995/10/18 08:42:23 deraadt Exp $
+.\"     @(#)strsep.3    8.1 (Berkeley) 6/9/93
 .\"
-.Dd April 19, 1991
+.Dd $Mdocdate: May 31 2007 $
 .Dt STRSEP 3
 .Os
 .Sh NAME
@@ -43,27 +41,37 @@
 .Sh SYNOPSIS
 .Fd #include <string.h>
 .Ft char *
-.Fn strsep "char **stringp" "char *delim"
+.Fn strsep "char **stringp" "const char *delim"
 .Sh DESCRIPTION
 The
 .Fn strsep
-locates in the null-terminated string at
-.Fa *stringp
-the first occurrence of any character in
-.Fa delim
-and replaces this with a
-.Ql \e0 ,
-records the location of the immediate following character in
+function locates, in the string referenced by
 .Fa *stringp ,
-then returns the original value of
+the first occurrence of any character in the string
+.Fa delim
+(or the terminating
+.Ql \e0
+character) and replaces it with a
+.Ql \e0 .
+The location of the next character after the delimiter character
+(or
+.Dv NULL ,
+if the end of the string was reached) is stored in
 .Fa *stringp .
-If no delimiter characters are found,
-.Fn strsep
-sets
+The original value of
 .Fa *stringp
+is returned.
+.Pp
+An
+.Dq empty
+field, i.e., one caused by two adjacent delimiter characters,
+can be detected by comparing the location referenced by the pointer returned
+by
+.Fn strsep
 to
-.Dv NULL ;
-if
+.Ql \e0 .
+.Pp
+If
 .Fa *stringp
 is initially
 .Dv NULL ,
@@ -73,20 +81,32 @@ returns
 .Sh EXAMPLES
 The following uses
 .Fn strsep
-to parse strings containing runs of white space,
-making up an argument vector:
+to parse a string, containing tokens delimited by whitespace, into an
+argument vector:
 .Bd -literal -offset indent
-char inputstring[100];
-char **argv[51], **ap = argv, *p, *val;
-/* set up inputstring */
-for (p = inputstring; p != NULL; ) {
-        while ((val = strsep(&p, " \et")) != NULL && *val == '\e0');
-        *ap++ = val;
+char **ap, *argv[10], *inputstring;
+
+for (ap = argv; ap < &argv[9] &&
+    (*ap = strsep(&inputstring, " \et")) != NULL;) {
+        if (**ap != '\e0')
+                ap++;
 }
-*ap = 0;
+*ap = NULL;
 .Ed
 .Sh HISTORY
 The
 .Fn strsep
-function is
-.Ud .
+function is intended as a replacement for the
+.Fn strtok
+function.
+While the
+.Fn strtok
+function should be preferred for portability reasons (it conforms to
+.St -ansiC )
+it is unable to handle empty fields, i.e., detect fields delimited by
+two adjacent delimiter characters, or to be used for more than a single
+string at a time.
+The
+.Fn strsep
+function first appeared in
+.Bx 4.4 .