MEMMEM(3)                                                               Linux Programmer's Manual                                                              MEMMEM(3)

NAME
       memmem - locate a substring

SYNOPSIS
       #define _GNU_SOURCE         /* See feature_test_macros(7) */
       #include <string.h>

       void *memmem(const void *haystack, size_t haystacklen,
                    const void *needle, 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 substring, 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 │
       └──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO
       This function is not specified in POSIX.1, but is present on a number of other systems.

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)

GNU                                                                            2021-03-22                                                                      MEMMEM(3)