1MEMMEM(3)                  Linux Programmer's Manual                 MEMMEM(3)
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NAME

6       memmem - locate a substring
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SYNOPSIS

9       #define _GNU_SOURCE         /* See feature_test_macros(7) */
10       #include <string.h>
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12       void *memmem(const void *haystack, size_t haystacklen,
13                    const void *needle, size_t needlelen);
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DESCRIPTION

16       The  memmem()  function  finds the start of the first occurrence of the
17       substring needle of length needlelen in the  memory  area  haystack  of
18       length haystacklen.
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RETURN VALUE

21       The  memmem()  function  returns a pointer to the beginning of the sub‐
22       string, or NULL if the substring is not found.
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ATTRIBUTES

25       For an  explanation  of  the  terms  used  in  this  section,  see  at‐
26       tributes(7).
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28       ┌────────────────────────────────────────────┬───────────────┬─────────┐
29       │Interface                                   │ Attribute     │ Value   │
30       ├────────────────────────────────────────────┼───────────────┼─────────┤
31       │memmem()                                    │ Thread safety │ MT-Safe │
32       └────────────────────────────────────────────┴───────────────┴─────────┘
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CONFORMING TO

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

39       In glibc 2.0, if needle is empty, memmem() returns  a  pointer  to  the
40       last byte of haystack.  This is fixed in glibc 2.1.
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SEE ALSO

43       bstring(3), strstr(3)
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COLOPHON

46       This  page  is  part of release 5.12 of the Linux man-pages project.  A
47       description of the project, information about reporting bugs,  and  the
48       latest     version     of     this    page,    can    be    found    at
49       https://www.kernel.org/doc/man-pages/.
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53GNU                               2021-03-22                         MEMMEM(3)
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