xref: /freebsd/lib/libc/string/strchr.3 (revision e5b786625f7f82a1fa91e41823332459ea5550f9)
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32.\"     @(#)strchr.3	8.2 (Berkeley) 4/19/94
33.\"
34.Dd February 13, 2013
35.Dt STRCHR 3
36.Os
37.Sh NAME
38.Nm strchr , strrchr , strchrnul
39.Nd locate character in string
40.Sh LIBRARY
41.Lb libc
42.Sh SYNOPSIS
43.In string.h
44.Ft "char *"
45.Fn strchr "const char *s" "int c"
46.Ft "char *"
47.Fn strrchr "const char *s" "int c"
48.Ft "char *"
49.Fn strchrnul "const char *s" "int c"
50.Sh DESCRIPTION
51The
52.Fn strchr
53function locates the first occurrence of
54.Fa c
55(converted to a
56.Vt char )
57in the string pointed to by
58.Fa s .
59The terminating null character is considered part of the string;
60therefore if
61.Fa c
62is
63.Ql \e0 ,
64the functions locate the terminating
65.Ql \e0 .
66.Pp
67The
68.Fn strrchr
69function is identical to
70.Fn strchr
71except it locates the last occurrence of
72.Fa c .
73.Pp
74The
75.Fn strchrnul
76function is identical to
77.Fn strchr
78except that if
79.Fa c
80is not found in
81.Fa s
82a pointer to the terminating
83.Ql \e0
84is returned.
85.Sh RETURN VALUES
86The functions
87.Fn strchr
88and
89.Fn strrchr
90return a pointer to the located character, or
91.Dv NULL
92if the character does not appear in the string.
93.Pp
94.Fn strchrnul
95returns a pointer to the terminating
96.Ql \e0
97if the character does not appear in the string.
98.Sh SEE ALSO
99.Xr memchr 3 ,
100.Xr memmem 3 ,
101.Xr strcspn 3 ,
102.Xr strpbrk 3 ,
103.Xr strsep 3 ,
104.Xr strspn 3 ,
105.Xr strstr 3 ,
106.Xr strtok 3 ,
107.Xr wcschr 3
108.Sh STANDARDS
109The functions
110.Fn strchr
111and
112.Fn strrchr
113conform to
114.St -isoC .
115The function
116.Fn strchrnul
117is a
118.Tn GNU
119extension.
120.Sh HISTORY
121The
122.Fn strchrnul
123function first appeared in glibc 2.1.1 and was added in
124.Fx 10.0 .
125