xref: /freebsd/lib/libc/string/strcasecmp.3 (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
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30.\"     @(#)strcasecmp.3	8.1 (Berkeley) 6/9/93
31.\" $FreeBSD$
32.\"
33.Dd June 9, 1993
34.Dt STRCASECMP 3
35.Os
36.Sh NAME
37.Nm strcasecmp ,
38.Nm strncasecmp
39.Nd compare strings, ignoring case
40.Sh LIBRARY
41.Lb libc
42.Sh SYNOPSIS
43.In strings.h
44.Ft int
45.Fn strcasecmp "const char *s1" "const char *s2"
46.Ft int
47.Fn strncasecmp "const char *s1" "const char *s2" "size_t len"
48.Sh DESCRIPTION
49The
50.Fn strcasecmp
51and
52.Fn strncasecmp
53functions
54compare the null-terminated strings
55.Fa s1
56and
57.Fa s2 .
58.Pp
59The
60.Fn strncasecmp
61compares at most
62.Fa len
63characters.
64.Sh RETURN VALUES
65The
66.Fn strcasecmp
67and
68.Fn strncasecmp
69return an integer greater than, equal to, or less than 0,
70according as
71.Fa s1
72is lexicographically greater than, equal to, or less than
73.Fa s2
74after translation of each corresponding character to lower-case.
75The strings themselves are not modified.
76The comparison is done using unsigned characters, so that
77.Sq Li \e200
78is greater than
79.Ql \e0 .
80.Sh SEE ALSO
81.Xr bcmp 3 ,
82.Xr memcmp 3 ,
83.Xr strcmp 3 ,
84.Xr strcoll 3 ,
85.Xr strxfrm 3 ,
86.Xr tolower 3
87.Sh HISTORY
88The
89.Fn strcasecmp
90and
91.Fn strncasecmp
92functions first appeared in
93.Bx 4.4 .
94Their prototypes existed previously in
95.In string.h
96before they were moved to
97.In strings.h
98for
99.St -p1003.1-2001
100compliance.
101