xref: /openbsd/lib/libc/string/strcmp.3 (revision 9490d37c)
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32.\"	$OpenBSD: strcmp.3,v 1.9 2007/05/31 19:19:32 jmc Exp $
33.\"
34.Dd $Mdocdate: May 31 2007 $
35.Dt STRCMP 3
36.Os
37.Sh NAME
38.Nm strcmp ,
39.Nm strncmp
40.Nd compare strings
41.Sh SYNOPSIS
42.Fd #include <string.h>
43.Ft int
44.Fn strcmp "const char *s1" "const char *s2"
45.Ft int
46.Fn strncmp "const char *s1" "const char *s2" "size_t len"
47.Sh DESCRIPTION
48The
49.Fn strcmp
50and
51.Fn strncmp
52functions lexicographically compare the NUL-terminated strings
53.Fa s1
54and
55.Fa s2 .
56.Sh RETURN VALUES
57The
58.Fn strcmp
59and
60.Fn strncmp
61return an integer greater than, equal to, or less than 0, according
62to whether the string
63.Fa s1
64is greater than, equal to, or less than the string
65.Fa s2 .
66The comparison is done using unsigned characters, so that
67.Ql \e200
68is greater than
69.Ql \e0 .
70.Pp
71.Fn strncmp
72compares at most
73.Fa len
74characters.
75.Sh SEE ALSO
76.Xr bcmp 3 ,
77.Xr memcmp 3 ,
78.Xr strcasecmp 3 ,
79.Xr strcoll 3 ,
80.Xr strxfrm 3
81.Sh STANDARDS
82The
83.Fn strcmp
84and
85.Fn strncmp
86functions conform to
87.St -ansiC .
88