xref: /freebsd/lib/libc/string/strstr.3 (revision 32eef9aeb1f39a1623cea55da147c89abbd5b9a5)
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36.\"     @(#)strstr.3	8.1 (Berkeley) 6/4/93
37.\" $FreeBSD$
38.\"
39.Dd June 4, 1993
40.Dt STRSTR 3
41.Os
42.Sh NAME
43.Nm strstr
44.Nd locate a substring in a string
45.Sh LIBRARY
46.Lb libc
47.Sh SYNOPSIS
48.In string.h
49.Ft char *
50.Fn strstr "const char *big" "const char *little"
51.Sh DESCRIPTION
52The
53.Fn strstr
54function
55locates the first occurrence of the null-terminated string
56.Fa little
57in the null-terminated string
58.Fa big .
59If
60.Fa little
61is the empty string,
62.Fn strstr
63returns
64.Fa big ;
65if
66.Fa little
67occurs nowhere in
68.Fa big ,
69.Fn strstr
70returns NULL;
71otherwise
72.Fn strstr
73returns a pointer to the first character of the first occurrence of
74.Fa little .
75.Sh SEE ALSO
76.Xr memchr 3 ,
77.Xr strchr 3 ,
78.Xr strcspn 3 ,
79.Xr strpbrk 3 ,
80.Xr strrchr 3 ,
81.Xr strsep 3 ,
82.Xr strspn 3 ,
83.Xr strtok 3
84.Sh STANDARDS
85The
86.Fn strstr
87function
88conforms to
89.St -isoC .
90