man3/memchr.3

   1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
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  23 .\" Modified Mon Apr 12 12:49:57 1993, David Metcalfe
  24 .\" Modified Sat Jul 24 18:56:22 1993, Rik Faith (faith@cs.unc.edu)
  25 .\" Modified Wed Feb 20 21:09:36 2002, Ian Redfern (redferni@logica.com)
  26 .\"
  27 .TH MEMCHR 3  2003-11-01 "" "Linux Programmer's Manual"
  28 .SH NAME
  29 memchr, memrchr \- scan memory for a character
  30 .SH SYNOPSIS
  31 .nf
  32 .B #include <string.h>
  33 .sp
  34 .BI "void *memchr(const void *" s ", int " c ", size_t " n );
  35 .sp
  36 .BI "void *memrchr(const void *" s ", int " c ", size_t " n );
  37 .fi
  38 .SH DESCRIPTION
  39 The
  40 .BR memchr ()
  41 function scans the first \fIn\fP bytes of the memory
  42 area pointed to by \fIs\fP for the character \fIc\fP.  The first byte to
  43 match \fIc\fP (interpreted as an unsigned character) stops the operation.
  44 .PP
  45 The
  46 .BR memrchr ()
  47 function is like the
  48 .BR memchr ()
  49 function,
  50 except that it searches backwards from the end of the \fIn\fP bytes
  51 pointed to by \fIs\fP instead of forwards from the front.
  52 .SH "RETURN VALUE"
  53 The \fBmemchr\fP() and \fBmemrchr\fP() functions return a pointer
  54 to the matching byte or NULL if the character does not occur in
  55 the given memory area.
  56 .SH "CONFORMING TO"
  57 The
  58 .BR memchr ()
  59 function conforms to SVr4, 4.3BSD, C89, C99, POSIX.1-2001.
  60 The
  61 .BR memrchr ()
  62 function is a GNU extension, available since glibc 2.1.91.
  63 .SH "SEE ALSO"
  64 .BR index (3),
  65 .BR rindex (3),
  66 .BR strchr (3),
  67 .BR strpbrk (3),
  68 .BR strrchr (3),
  69 .BR strsep (3),
  70 .BR strspn (3),
  71 .BR strstr (3),
  72 .BR wmemchr (3)