xref: /openbsd/lib/libc/string/strcmp.3 (revision 8529ddd3)
1.\"	$OpenBSD: strcmp.3,v 1.14 2013/07/17 05:42:11 schwarze Exp $
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34.Dd $Mdocdate: July 17 2013 $
35.Dt STRCMP 3
36.Os
37.Sh NAME
38.Nm strcmp ,
39.Nm strncmp
40.Nd compare strings
41.Sh SYNOPSIS
42.In 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 .
56The
57.Fn strncmp
58function compares at most
59.Fa len
60characters.
61.Sh RETURN VALUES
62The
63.Fn strcmp
64and
65.Fn strncmp
66functions return an integer greater than, equal to, or less than 0, according
67to whether the string
68.Fa s1
69is greater than, equal to, or less than the string
70.Fa s2 .
71The comparison is done using unsigned characters, so that
72.Ql \e200
73is greater than
74.Ql \e0 .
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.Xr wcscmp 3
82.Sh STANDARDS
83The
84.Fn strcmp
85and
86.Fn strncmp
87functions conform to
88.St -ansiC .
89.Sh HISTORY
90The
91.Fn strcmp
92function first appeared in the Programmer's Workbench (PWB/UNIX)
93and was ported to
94.At v7 ;
95.Fn strncmp
96first appeared in
97.At v7 .
98