1.\"	$NetBSD: islower.3,v 1.14 2008/04/17 16:25:36 apb Exp $
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3.\" Copyright (c) 1991 The Regents of the University of California.
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6.\" This code is derived from software contributed to Berkeley by
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8.\" Processing Systems.
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34.\"     @(#)islower.3	5.2 (Berkeley) 6/29/91
35.\"
36.Dd April 17, 2008
37.Dt ISLOWER 3
38.Os
39.Sh NAME
40.Nm islower
41.Nd lower-case character test
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In ctype.h
46.Ft int
47.Fn islower "int c"
48.Sh DESCRIPTION
49The
50.Fn islower
51function tests for any lower-case letter
52.\" or any of an
53.\" implementation-defined set of characters
54for which none of
55.Xr iscntrl 3 ,
56.Xr isdigit 3 ,
57.Xr ispunct 3 ,
58or
59.Xr isspace 3
60is true.
61In the
62.Em ``C''
63locale,
64.Fn islower
65returns true only for the characters defined as lower-case letters.
66.Sh RETURN VALUES
67The
68.Fn islower
69function returns zero if the character tests false and
70returns non-zero if the character tests true.
71.Sh SEE ALSO
72.Xr ctype 3 ,
73.Xr isalnum 3 ,
74.Xr isalpha 3 ,
75.Xr isascii 3 ,
76.Xr isblank 3 ,
77.Xr iscntrl 3 ,
78.Xr isdigit 3 ,
79.Xr isgraph 3 ,
80.Xr isprint 3 ,
81.Xr ispunct 3 ,
82.Xr isspace 3 ,
83.Xr isupper 3 ,
84.Xr isxdigit 3 ,
85.Xr stdio 3 ,
86.Xr toascii 3 ,
87.Xr tolower 3 ,
88.Xr toupper 3 ,
89.Xr ascii 7
90.Sh STANDARDS
91The
92.Fn islower
93function conforms to
94.St -ansiC .
95.Sh CAVEATS
96The argument to
97.Fn islower
98must be
99.Dv EOF
100or representable as an
101.Vt unsigned char ;
102otherwise, the behavior is undefined.
103See the
104.Sx CAVEATS
105section of
106.Xr ctype 3
107for more details.
108