memrchr

(3)

scan memory for a character

Library functionsmanpages-dev 6.9.1-1also documents memchr, rawmemchr

#include <string.h> void *memchr(const void s[.n], int c, size_t n); void *memrchr(const void s[.n], int c, size_t n); [[deprecated]] void *rawmemchr(const void *s, int c); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): memrchr(), rawmemchr(): _GNU_SOURCE

LIBRARY

Standard C library (libc, -lc)

DESCRIPTION

The memchr() function scans the initial n bytes of the memory area pointed to by s for the first instance of c. Both c and the bytes of the memory area pointed to by s are interpreted as unsigned char.

The memrchr() function is like the memchr() function, except that it searches backward from the end of the n bytes pointed to by s instead of forward from the beginning.

The rawmemchr() function is similar to memchr(), but it assumes (i.e., the programmer knows for certain) that an instance of c lies somewhere in the memory area starting at the location pointed to by s. If an instance of c is not found, the behavior is undefined. Use either strlen(3) or memchr(3) instead.

RETURN VALUE

The memchr() and memrchr() functions return a pointer to the matching byte or NULL if the character does not occur in the given memory area.

The rawmemchr() function returns a pointer to the matching byte.

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
memchr (), memrchr (), rawmemchr ()	Thread safety	MT-Safe

STANDARDS

memchr(): C11, POSIX.1-2008.
memrchr()
rawmemchr(): GNU.

HISTORY

memchr(): POSIX.1-2001, C89, SVr4, 4.3BSD.
memrchr(): glibc 2.2.
rawmemchr(): glibc 2.1.