xref: /freebsd/lib/libc/string/strcmp.3 (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
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32.\"     @(#)strcmp.3	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD$
34.\"
35.Dd October 11, 2001
36.Dt STRCMP 3
37.Os
38.Sh NAME
39.Nm strcmp ,
40.Nm strncmp
41.Nd compare strings
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In string.h
46.Ft int
47.Fn strcmp "const char *s1" "const char *s2"
48.Ft int
49.Fn strncmp "const char *s1" "const char *s2" "size_t len"
50.Sh DESCRIPTION
51The
52.Fn strcmp
53and
54.Fn strncmp
55functions
56lexicographically compare the null-terminated strings
57.Fa s1
58and
59.Fa s2 .
60.Pp
61The
62.Fn strncmp
63function
64compares not more than
65.Fa len
66characters.
67Because
68.Fn strncmp
69is designed for comparing strings rather than binary data,
70characters that appear after a
71.Ql \e0
72character are not compared.
73.Sh RETURN VALUES
74The
75.Fn strcmp
76and
77.Fn strncmp
78return an integer greater than, equal to, or less than 0, according
79as the string
80.Fa s1
81is greater than, equal to, or less than the string
82.Fa s2 .
83The comparison is done using unsigned characters, so that
84.Ql \e200
85is greater than
86.Ql \e0 .
87.Sh SEE ALSO
88.Xr bcmp 3 ,
89.Xr memcmp 3 ,
90.Xr strcasecmp 3 ,
91.Xr strcoll 3 ,
92.Xr strxfrm 3
93.Sh STANDARDS
94The
95.Fn strcmp
96and
97.Fn strncmp
98functions
99conform to
100.St -isoC .
101