xref: /dragonfly/lib/libc/string/strchr.3 (revision e8c03636)
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32.\"     @(#)strchr.3	8.2 (Berkeley) 4/19/94
33.\" $FreeBSD: src/lib/libc/string/strchr.3,v 1.13 2007/01/09 00:28:12 imp Exp $
34.\"
35.Dd March 3, 2013
36.Dt STRCHR 3
37.Os
38.Sh NAME
39.Nm strchr ,
40.Nm strrchr ,
41.Nm strrchrnul
42.Nd locate character in string
43.Sh LIBRARY
44.Lb libc
45.Sh SYNOPSIS
46.In string.h
47.Ft "char *"
48.Fn strchr "const char *s" "int c"
49.Ft "char *"
50.Fn strrchr "const char *s" "int c"
51.Ft "char *"
52.Fn strchrnul "const char *s" "int c"
53.Sh DESCRIPTION
54The
55.Fn strchr
56function locates the first occurrence of
57.Fa c
58(converted to a
59.Vt char )
60in the string pointed to by
61.Fa s .
62The terminating nul character is considered part of the string;
63therefore if
64.Fa c
65is
66.Ql \e0 ,
67the functions locate the terminating
68.Ql \e0 .
69.Pp
70The
71.Fn strrchr
72function is identical to
73.Fn strchr
74except it locates the last occurrence of
75.Fa c .
76.Pp
77The
78.Fn strchrnul
79function is identical to
80.Fn strchr
81except that it returns a pointer to the terminating nul character of
82.Fa s
83instead of
84.Dv NULL
85if
86.Fa c
87is not found.
88.Sh RETURN VALUES
89The functions
90.Fn strchr
91and
92.Fn strrchr
93return a pointer to the located character, or
94.Dv NULL
95if the character does not appear in the string.
96.Fn strchrnul
97returns a pointer to the located character, or to the terminating nul
98character of
99.Fa s
100if
101.Fa c
102is not found in the string.
103.Sh SEE ALSO
104.Xr memchr 3 ,
105.Xr memmem 3 ,
106.Xr strcspn 3 ,
107.Xr strpbrk 3 ,
108.Xr strsep 3 ,
109.Xr strspn 3 ,
110.Xr strstr 3 ,
111.Xr strtok 3
112.Sh STANDARDS
113The functions
114.Fn strchr
115and
116.Fn strrchr
117conform to
118.St -isoC .
119.Pp
120The
121.Fn strchrnul
122function first appeared in glibc 2.1.1
123