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Manual Pages  — MEMCHR


memchr – locate byte in byte string



Standard C Library (libc, -lc)


#include <string.h>

void *
memchr(const void *b, int c, size_t len);

void *
memrchr(const void *b, int c, size_t len);


The memchr() function locates the first occurrence of c (converted to an unsigned char) in string b.

The memrchr() function behaves like memchr(), except that it locates the last occurrence of c in string b.


The memchr() and memrchr() functions return a pointer to the byte located, or NULL if no such byte exists within len bytes.


memmem(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strstr(3), strtok(3), wmemchr(3)


The memchr() function conforms to ISO/IEC 9899:1990 ("ISO C90").

The memrchr() function is a GNU extension and conforms to no standard.


The memrchr() function first appeared in GNU libc 2.1.91, this implementation first appeared in FreeBSD 6.4, coming from OpenBSD 4.3 .

MEMCHR (3) April 9, 2008

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