MEMCHR(3) | Library Functions Manual | MEMCHR(3)

# NAME

`memchr`, `memrchr` — locate byte in byte string

# SYNOPSIS

`#include <string.h>`

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

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

# DESCRIPTION

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.

# RETURN VALUES

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

# SEE ALSO

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

# STANDARDS

The `memchr`() function conforms to ANSI X3.159-1989 (“ANSI C89”).

The `memrchr`() function is an OpenBSD extension.

# HISTORY

The `memchr`() function first appeared in AT&T System V UNIX and was reimplemented for 4.3BSD.

December 11, 2024 | Debian