memmem(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ATTRIBUTES | CONFORMING TO | BUGS | SEE ALSO | COLOPHON

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

NAME         top

       memmem - locate a substring

SYNOPSIS         top

       #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         top

       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         top

       The memmem() function returns a pointer to the beginning of the
       substring, or NULL if the substring is not found.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).

       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │Interface                             Attribute     Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │memmem()                              │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO         top

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

BUGS         top

       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         top

       bstring(3), strstr(3)

COLOPHON         top

       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/.

GNU                            2021-03-22                      MEMMEM(3)

Pages that refer to this page: bstring(3)memchr(3)strstr(3)