xref: /freebsd/lib/libc/string/strstr.3 (revision 7f3dea244c40159a41ab22da77a434d7c5b5e85a)
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5.\" Chris Torek and the American National Standards Committee X3,
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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 SYNOPSIS
46.Fd #include <string.h>
47.Ft char *
48.Fn strstr "const char *big" "const char *little"
49.Sh DESCRIPTION
50The
51.Fn strstr
52function
53locates the first occurrence of the null-terminated string
54.Fa little
55in the null-terminated string
56.Fa big .
57If
58.Fa little
59is the empty string,
60.Fn strstr
61returns
62.Fa big ;
63if
64.Fa little
65occurs nowhere in
66.Fa big ,
67.Fn strstr
68returns NULL;
69otherwise
70.Fn strstr
71returns a pointer to the first character of the first occurrence of
72.Fa little .
73.Sh SEE ALSO
74.Xr index 3 ,
75.Xr memchr 3 ,
76.Xr rindex 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 -ansiC .
90