xref: /netbsd-src/lib/libc/string/strchr.3 (revision a411c1a5570043df8f0e4be44bdd6cecbf39a499)
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32.\"     from: @(#)strchr.3	8.2 (Berkeley) 4/19/94
33.\"	$NetBSD: strchr.3,v 1.15 2023/01/31 01:42:32 simonb Exp $
34.\"
35.Dd November 27, 2020
36.Dt STRCHR 3
37.Os
38.Sh NAME
39.Nm strchr, strchrnul
40.Nd locate character in string
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.In string.h
45.Ft char *
46.Fn strchr "const char *s" "int c"
47.Ft char *
48.Fn strchrnul "const char *s" "int c"
49.Sh DESCRIPTION
50The
51.Fn strchr
52and
53.Fn strchrnul
54functions locate the first occurrence of
55.Ar c
56in the string pointed to by
57.Ar s .
58The terminating
59.Dv NUL
60character is considered part of the string.
61If
62.Fa c
63is
64.Ql \e0 ,
65.Fn strchr
66and
67.Fn strchrnul
68locate the terminating
69.Ql \e0 .
70.Sh RETURN VALUES
71The function
72.Fn strchr
73returns a pointer to the located character, or
74.Dv NULL
75if the character does not appear in the string.
76The function
77.Fn strchrnul
78returns a pointer to the located character, or
79a pointer to the
80.Dv NUL
81terminating character of the string if the character does not appear
82in the string.
83.Sh EXAMPLES
84After the following call to
85.Fn strchr ,
86.Va p
87will point to the string
88.Qq oobar :
89.Bd -literal -offset indent
90char *p;
91char *s = "foobar";
92
93p = strchr(s, 'o');
94.Ed
95.Sh SEE ALSO
96.Xr index 3 ,
97.Xr memchr 3 ,
98.Xr rindex 3 ,
99.Xr strcspn 3 ,
100.Xr strpbrk 3 ,
101.Xr strrchr 3 ,
102.Xr strsep 3 ,
103.Xr strspn 3 ,
104.Xr strstr 3 ,
105.Xr strtok 3
106.Sh STANDARDS
107The
108.Fn strchr
109function
110conforms to
111.St -ansiC .
112.Sh HISTORY
113The
114.Fn strchrnul
115first appeared in glibc 2.1.1 and was added to
116.Fx 10
117and
118.Nx 8 .
119