1 files changed, 43 insertions, 20 deletions

diff --git a/src/lib/libc/string/strcspn.3 b/src/lib/libc/string/strcspn.3
index cc9e5c2fe3..70c8ef7612 100644
--- a/src/lib/libc/string/strcspn.3
+++ b/src/lib/libc/string/strcspn.3
@@ -1,3 +1,5 @@
+.\"     $OpenBSD: strcspn.3,v 1.10 2011/07/25 00:38:53 schwarze Exp $
+.\"
 .\" Copyright (c) 1990, 1991 The Regents of the University of California.
 .\" All rights reserved.
 .\"
@@ -13,11 +15,7 @@
 .\" 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.
 .\"
@@ -33,10 +31,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     from: @(#)strcspn.3     5.3 (Berkeley) 6/29/91
-.\"     $Id: strcspn.3,v 1.1.1.1 1995/10/18 08:42:22 deraadt Exp $
-.\"
-.Dd June 29, 1991
+.Dd $Mdocdate: July 25 2011 $
 .Dt STRCSPN 3
 .Os
 .Sh NAME
@@ -49,37 +44,65 @@
 .Sh DESCRIPTION
 The
 .Fn strcspn
-function
-spans the initial part of the null-terminated string
+function spans the initial part of the NUL-terminated string
 .Fa s
 as long as the characters from
 .Fa s
 do not occur in string
 .Fa charset
-(it
-spans the
+(it spans the
 .Em complement
 of
 .Fa charset ) .
 .Sh RETURN VALUES
 The
 .Fn strcspn
-function
-returns the number of characters spanned.
+function returns the number of characters spanned.
+.Sh EXAMPLES
+The following call to
+.Fn strcspn
+will return 3, since the first three characters of string
+.Fa s
+do not occur in string
+.Fa charset :
+.Bd -literal -offset indent
+char *s = "foobar";
+char *charset = "bar";
+size_t span;
+
+span = strcspn(s, charset);
+.Ed
+.Pp
+The following removes the first (if any) newline character from string
+.Fa line .
+This is useful for trimming the newline after a
+.Xr fgets 3
+call.
+.Bd -literal -offset indent
+char line[BUFSIZ];
+
+if (fgets(line, sizeof(line), fp) != NULL)
+        line[strcspn(line, "\en")] = '\e0';
+.Ed
 .Sh SEE ALSO
-.Xr index 3 ,
 .Xr memchr 3 ,
-.Xr rindex 3 ,
 .Xr strchr 3 ,
 .Xr strpbrk 3 ,
 .Xr strrchr 3 ,
 .Xr strsep 3 ,
 .Xr strspn 3 ,
 .Xr strstr 3 ,
-.Xr strtok 3
+.Xr strtok 3 ,
+.Xr wcscspn 3
 .Sh STANDARDS
 The
 .Fn strcspn
-function
-conforms to
+function conforms to
 .St -ansiC .
+.Sh HISTORY
+The
+.Fn strcspn
+function first appeared in
+.At III
+and was reimplemented for
+.Bx 4.3 Tahoe .