xref: /netbsd-src/lib/libc/string/strcmp.3 (revision c41a4eebefede43f6950f838a387dc18c6a431bf)
1.\" Copyright (c) 1990, 1991 The Regents of the University of California.
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4.\" This code is derived from software contributed to Berkeley by
5.\" Chris Torek and the American National Standards Committee X3,
6.\" on Information Processing Systems.
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36.\"     from: @(#)strcmp.3	5.6 (Berkeley) 6/29/91
37.\"	$NetBSD: strcmp.3,v 1.4 1997/11/14 02:04:53 mrg Exp $
38.\"
39.Dd June 29, 1991
40.Dt STRCMP 3
41.Os
42.Sh NAME
43.Nm strcmp ,
44.Nm strncmp
45.Nd compare strings
46.Sh SYNOPSIS
47.Fd #include <string.h>
48.Ft int
49.Fn strcmp "const char *s1" "const char *s2"
50.Ft int
51.Fn strncmp "const char *s1" "const char *s2" "size_t len"
52.Sh DESCRIPTION
53The
54.Fn strcmp
55and
56.Fn strncmp
57functions
58lexicographically compare the null-terminated strings
59.Fa s1
60and
61.Fa s2 .
62.Sh RETURN VALUES
63The
64.Fn strcmp
65and
66.Fn strncmp
67return an integer greater than, equal to, or less than 0, according
68as the string
69.Fa s1
70is greater than, equal to, or less than the string
71.Fa s2 .
72The comparison is done using unsigned characters, so that
73.Ql \e200
74is greater than
75.Ql \e0 .
76.Pp
77The
78.Fn strncmp
79compares not more than
80.Fa len
81characters.
82.Sh SEE ALSO
83.Xr bcmp 3 ,
84.Xr memcmp 3 ,
85.Xr strcasecmp 3 ,
86.Xr strcoll 3 ,
87.Xr strxfrm 3
88.Sh STANDARDS
89The
90.Fn strcmp
91and
92.Fn strncmp
93functions
94conform to
95.St -ansiC .
96