memmem

       #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 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 |
       +----------+---------------+---------+
CONFORMING TO
       This function is a GNU extension.

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
       strstr(3)

COLOPHON
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       description  of  the project, information about reporting bugs, and the
       latest    version    of    this    page,    can     be     found     at
       http://www.kernel.org/doc/man-pages/.

GNU                               2015-03-02                         MEMMEM(3)
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