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)

COLOPHON

       This page is part of release 5.13 of the Linux man-pages project.  A  description  of  the
       project,  information  about  reporting  bugs, and the latest version of this page, can be
       found at https://www.kernel.org/doc/man-pages/.