xref: /freebsd/lib/libc/string/strcasecmp.3 (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
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34.\"     @(#)strcasecmp.3	8.1 (Berkeley) 6/9/93
35.\"
36.Dd June 9, 1993
37.Dt STRCASECMP 3
38.Os
39.Sh NAME
40.Nm strcasecmp ,
41.Nm strncasecmp
42.Nd compare strings, ignoring case
43.Sh SYNOPSIS
44.Fd #include <string.h>
45.Ft int
46.Fn strcasecmp "const char *s1" "const char *s2"
47.Ft int
48.Fn strncasecmp "const char *s1" "const char *s2" "size_t len"
49.Sh DESCRIPTION
50The
51.Fn strcasecmp
52and
53.Fn strncasecmp
54functions
55compare the null-terminated strings
56.Fa s1
57and
58.Fa s2
59and return an integer greater than, equal to, or less than 0,
60according as
61.Fa s1
62is lexicographically greater than, equal to, or less than
63.Fa s2
64after translation of each corresponding character to lower-case.
65The strings themselves are not modified.
66The comparison is done using unsigned characters, so that
67.Sq Li \e200
68is greater than
69.Ql \e0 .
70.Pp
71The
72.Fn strncasecmp
73compares at most
74.Fa len
75characters.
76.Sh SEE ALSO
77.Xr bcmp 3 ,
78.Xr memcmp 3 ,
79.Xr strcmp 3 ,
80.Xr strcoll 3 ,
81.Xr strxfrm 3
82.Sh HISTORY
83The
84.Fn strcasecmp
85and
86.Fn strncasecmp
87functions first appeared in
88.Bx 4.4 .
89