Section: Linux Programmer's Manual (3)
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memchr, memrchr, rawmemchr - scan memory for a character
void *memchr(const void *s, int c, size_t n);
void *memrchr(const void *s, int c, size_t n);
void *rawmemchr(const void *s, int c);
Feature Test Macro Requirements for glibc (see
function scans the first n bytes of the memory
area pointed to by s for the character c.
The first byte to
match c (interpreted as an unsigned character) stops the operation.
function is like the
except that it searches backwards from the end of the n bytes
pointed to by s instead of forwards from the beginning.
function is similar to
it assumes (i.e., the programmer knows for certain)
that the character
lies somewhere in the string
and so performs an optimized search
for the character
(i.e., no checking for the terminating null byte, or use of an argument,
to limit the range of the search).
If the character
is not in the string
may proceed 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
terminating null byte:
char *p = rawmemchr(s, '\0');
functions return a pointer
to the matching byte or NULL if the character does not occur in
the given memory area.
function returns a pointer to the matching byte, if one is found.
If no matching byte is found, the result is unspecified.
first appeared in glibc in version 2.1.
first appeared in glibc in version 2.2.
function conforms to SVr4, 4.3BSD, C89, C99, POSIX.1-2001.
function is a GNU extension, available since glibc 2.1.91.
function is a GNU extension, available since glibc 2.1.
This page is part of release 3.27 of the Linux
A description of the project,
and information about reporting bugs,
can be found at
- RETURN VALUE
- CONFORMING TO
- SEE ALSO
This document was created by
using the manual pages.