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

   strstr(3)

COLOPHON

   This  page  is  part of release 4.09 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/.





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