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[thirdparty/man-pages.git] / man3 / memchr.3

diff --git a/man3/memchr.3 b/man3/memchr.3
index 831d8266fb9b57e0b101fc9dcbcdb5d9c5da85eb..c67689ec2f7311364716c002edda17b795ebf860 100644 (file)
--- a/man3/memchr.3
+++ b/man3/memchr.3
@@ -2,6 +2,7 @@
 .\" and Copyright (c) 2008 Linux Foundation, written by Michael Kerrisk
 .\"     <mtk.manpages@gmail.com>
 .\"
+.\" %%%LICENSE_START(VERBATIM)
 .\" Permission is granted to make and distribute verbatim copies of this
 .\" manual provided the copyright notice and this permission notice are
 .\" preserved on all copies.
@@ -21,13 +22,14 @@
 .\"
 .\" Formatted or processed versions of this manual, if unaccompanied by
 .\" the source, must acknowledge the copyright and authors of this work.
+.\" %%%LICENSE_END
 .\"
 .\" Modified Mon Apr 12 12:49:57 1993, David Metcalfe
 .\" Modified Sat Jul 24 18:56:22 1993, Rik Faith (faith@cs.unc.edu)
 .\" Modified Wed Feb 20 21:09:36 2002, Ian Redfern (redferni@logica.com)
 .\" 2008-07-09, mtk, add rawmemchr()
 .\"
-.TH MEMCHR 3  2008-07-09 "" "Linux Programmer's Manual"
+.TH MEMCHR 3  2012-04-23 "" "Linux Programmer's Manual"
 .SH NAME
 memchr, memrchr, rawmemchr \- scan memory for a character
 .SH SYNOPSIS
@@ -46,56 +48,61 @@ Feature Test Macro Requirements for glibc (see
 .BR feature_test_macros (7)):
 .in
 .sp
+.BR memrchr (),
 .BR rawmemchr ():
 _GNU_SOURCE
 .SH DESCRIPTION
 The
 .BR memchr ()
-function scans the first \fIn\fP bytes of the memory
-area pointed to by \fIs\fP for the character \fIc\fP.
-The first byte to
-match \fIc\fP (interpreted as an unsigned character) stops the operation.
+function scans the initial
+.I n
+bytes of the memory
+area pointed to by
+.I s
+for the first instance of
+.IR c .
+Both
+.I c
+and the bytes of the memory area pointed to by
+.I s
+are interpreted as
+.IR "unsigned char" .
 .PP
 The
 .BR memrchr ()
 function is like the
 .BR memchr ()
 function,
-except that it searches backwards from the end of the \fIn\fP bytes
-pointed to by \fIs\fP instead of forwards from the beginning.
+except that it searches backward from the end of the
+.I n
+bytes pointed to by
+.I s
+instead of forward from the beginning.
 
 The
 .BR rawmemchr ()
 function is similar to
 .BR memchr ():
 it assumes (i.e., the programmer knows for certain)
-that the character
+that an instance of
 .I c
-lies somewhere in the string
+lies somewhere in the memory area starting at the location pointed to by
 .IR s ,
-and so performs an optimized search
-for the character
-.IR c 
-(i.e., no checking for the terminating null byte, or use of an argument,
-.IR n ,
-to limit the range of the search).
-If the chararacter
+and so performs an optimized search for
+.IR c
+(i.e., no use of a count argument to limit the range of the search).
+If an instance of
 .I c
-is not in the string
-.IR s ,
-then
-.BR rawmemchr () 
-may proceeed to search beyond the end of the string,
-and the result is unspecified.
-The folowing call is a fast means of locating a string's
+is not found, the results are unpredictable.
+The following call is a fast means of locating a string's
 terminating null byte:
 .in +4n
 .nf
 
-char *p; rawmemchr(s,\ '\\0');
+char *p = rawmemchr(s,\ \(aq\\0\(aq);
 .fi
 .in
-.SH "RETURN VALUE"
+.SH RETURN VALUE
 The
 .BR memchr ()
 and
@@ -108,7 +115,13 @@ The
 .BR rawmemchr ()
 function returns a pointer to the matching byte, if one is found.
 If no matching byte is found, the result is unspecified.
-.SH "CONFORMING TO"
+.SH VERSIONS
+.BR rawmemchr ()
+first appeared in glibc in version 2.1.
+
+.BR memrchr ()
+first appeared in glibc in version 2.2.
+.SH CONFORMING TO
 The
 .BR memchr ()
 function conforms to SVr4, 4.3BSD, C89, C99, POSIX.1-2001.
@@ -120,7 +133,8 @@ function is a GNU extension, available since glibc 2.1.91.
 The
 .BR rawmemchr ()
 function is a GNU extension, available since glibc 2.1.
-.SH "SEE ALSO"
+.SH SEE ALSO
+.BR ffs (3),
 .BR index (3),
 .BR rindex (3),
 .BR strchr (3),