xref: /freebsd/lib/libc/string/memmem.3 (revision 6050c8fe05cff5f6b5d0191db51223f86b7c04f0)
1.\" Copyright (c) 2005 Pascal Gloor <pascal.gloor@spale.com>
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27\" $FreeBSD$
28.\"
29.Dd August 24, 2005
30.Dt MEMMEM 3
31.Os
32.Sh NAME
33.Nm memmem
34.Nd locate a byte substring in a byte string
35.Sh LIBRARY
36.Lb libc
37.Sh SYNOPSIS
38.In string.h
39.Ft void *
40.Fn memmem "const char *big" "size_t big_len" \
41"const char *little" "size_t little_len"
42.Sh DESCRIPTION
43The
44.Fn memmem
45function
46locates the first occurrence of the byte string
47.Fa little
48in the byte string
49.Fa big .
50.Sh RETURN VALUES
51If
52.Fa big_len
53is smaller than
54.Fa little_len ,
55if
56.Fa little_len
57is 0, if
58.Fa big_len
59is 0 or if
60.Fa little
61occurs nowhere in
62.Fa big ,
63.Dv NULL
64is returned;
65otherwise a pointer to the first character of the first occurrence of
66.Fa little
67is returned.
68.Sh SEE ALSO
69.Xr memchr 3 ,
70.Xr strchr 3 ,
71.Xr strstr 3
72.Sh CONFORMING TO
73.Fn memmem
74is a GNU extension.
75.Sh HISTORY
76The
77.Fn memmem
78function first appeared in
79.Fx 6.0 .
80.Sh AUTHOR
81Pascal Gloor <pascal.gloor@spale.com>
82.Sh BUGS
83This function was broken in Linux libc up to and including version 5.0.9
84and in GNU libc prior to version 2.1.
85