xref: /freebsd/lib/libc/string/strchr.3 (revision e8e8c939350bdf3c228a411caa9660c607c27a11)
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32.\"     @(#)strchr.3	8.2 (Berkeley) 4/19/94
33.\" $FreeBSD$
34.\"
35.Dd February 13, 2013
36.Dt STRCHR 3
37.Os
38.Sh NAME
39.Nm strchr , strrchr , 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 strrchr "const char *s" "int c"
49.Ft "char *"
50.Fn strchrnul "const char *s" "int c"
51.Sh DESCRIPTION
52The
53.Fn strchr
54function locates the first occurrence of
55.Fa c
56(converted to a
57.Vt char )
58in the string pointed to by
59.Fa s .
60The terminating null character is considered part of the string;
61therefore if
62.Fa c
63is
64.Ql \e0 ,
65the functions locate the terminating
66.Ql \e0 .
67.Pp
68The
69.Fn strrchr
70function is identical to
71.Fn strchr
72except it locates the last occurrence of
73.Fa c .
74.Pp
75The
76.Fn strchrnul
77function is identical to
78.Fn strchr
79except that if
80.Fa c
81is not found in
82.Fa s
83a pointer to the terminating
84.Ql \e0
85is returned.
86.Sh RETURN VALUES
87The functions
88.Fn strchr
89and
90.Fn strrchr
91return a pointer to the located character, or
92.Dv NULL
93if the character does not appear in the string.
94.Pp
95.Fn strchrnul
96returns a pointer to the terminating
97.Ql \e0
98if the character does not appear in the string.
99.Sh SEE ALSO
100.Xr memchr 3 ,
101.Xr memmem 3 ,
102.Xr strcspn 3 ,
103.Xr strpbrk 3 ,
104.Xr strsep 3 ,
105.Xr strspn 3 ,
106.Xr strstr 3 ,
107.Xr strtok 3 ,
108.Xr wcschr 3
109.Sh STANDARDS
110The functions
111.Fn strchr
112and
113.Fn strrchr
114conform to
115.St -isoC .
116The function
117.Fn strchrnul
118is a
119.Tn GNU
120extension.
121.Sh HISTORY
122The
123.Fn strchrnul
124function first appeared in glibc 2.1.1 and was added in
125.Fx 10.0 .
126