xref: /freebsd/lib/libc/string/strcasecmp.3 (revision 4f29da19bd44f0e99f021510460a81bf754c21d2)
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34.\"     @(#)strcasecmp.3	8.1 (Berkeley) 6/9/93
35.\" $FreeBSD$
36.\"
37.Dd June 9, 1993
38.Dt STRCASECMP 3
39.Os
40.Sh NAME
41.Nm strcasecmp ,
42.Nm strncasecmp
43.Nd compare strings, ignoring case
44.Sh LIBRARY
45.Lb libc
46.Sh SYNOPSIS
47.In strings.h
48.Ft int
49.Fn strcasecmp "const char *s1" "const char *s2"
50.Ft int
51.Fn strncasecmp "const char *s1" "const char *s2" "size_t len"
52.Sh DESCRIPTION
53The
54.Fn strcasecmp
55and
56.Fn strncasecmp
57functions
58compare the null-terminated strings
59.Fa s1
60and
61.Fa s2 .
62.Pp
63The
64.Fn strncasecmp
65compares at most
66.Fa len
67characters.
68.Sh RETURN VALUES
69The
70.Fn strcasecmp
71and
72.Fn strncasecmp
73return an integer greater than, equal to, or less than 0,
74according as
75.Fa s1
76is lexicographically greater than, equal to, or less than
77.Fa s2
78after translation of each corresponding character to lower-case.
79The strings themselves are not modified.
80The comparison is done using unsigned characters, so that
81.Sq Li \e200
82is greater than
83.Ql \e0 .
84.Sh SEE ALSO
85.Xr bcmp 3 ,
86.Xr memcmp 3 ,
87.Xr strcmp 3 ,
88.Xr strcoll 3 ,
89.Xr strxfrm 3 ,
90.Xr tolower 3
91.Sh HISTORY
92The
93.Fn strcasecmp
94and
95.Fn strncasecmp
96functions first appeared in
97.Bx 4.4 .
98Their prototypes existed previously in
99.In string.h
100before they were moved to
101.In strings.h
102for
103.St -p1003.1-2001
104compliance.
105