NAME
memmem —
locate a byte substring in a byte
string
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include
<string.h>
void *
memmem(const void *big,
size_t big_len, const void
*little, size_t little_len);
DESCRIPTION
The
memmem()
function locates the first occurrence of the byte string
little in the byte string
big.
RETURN VALUES
If little_len is zero
big is returned (that is, an empty little is deemed to
match at the beginning of big); if little occurs
nowhere in big, NULL is
returned; otherwise a pointer to the first character of the first occurrence
of little is returned.
SEE ALSO
CONFORMING TO
memmem() started as a GNU extension but is
now available in at least the GNU, musl, bionic, OpenBSD, NetBSD, macOS, and
illumos C runtime libraries.
HISTORY
The memmem() function first appeared in
FreeBSD 6.0. It was replaced with an optimized O(n)
implementation from the musl libc project in FreeBSD
12.0. Pascal Gloor
<pascal.gloor@spale.com>
provided this man page along with the previous implementation.
BUGS
This function was broken in Linux libc up to and including version
5.0.9 and in GNU libc prior to version 2.1. Prior to
FreeBSD 11.0 memmem returned
NULL when little_len equals
0.