memmem(3) Library Functions Manual memmem(3)
NAME
memmem - locate a substring
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <string.h>
void *memmem(const void haystack[.haystacklen], size_t haystacklen,
const void needle[.needlelen], size_t needlelen);
DESCRIPTION
The memmem() function finds the start of the first occurrence of the
substring needle of length needlelen in the memory area haystack of
length haystacklen.
RETURN VALUE
The memmem() function returns a pointer to the beginning of the sub-
string, or NULL if the substring is not found.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌────────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────────────┼───────────────┼─────────┤
│ memmem() │ Thread safety │ MT-Safe │
└────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
None.
HISTORY
musl libc 0.9.7; FreeBSD 6.0, OpenBSD 5.4, NetBSD, Illumos.
BUGS
In glibc 2.0, if needle is empty, memmem() returns a pointer to the last
byte of haystack. This is fixed in glibc 2.1.
SEE ALSO
bstring(3), strstr(3)
Linux man-pages 6.9.1 2024-05-02 memmem(3)
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