freebsd-dev/lib/libc/locale/islower.3

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.\"     @(#)islower.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
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.Dd October 6, 2002
.Dt ISLOWER 3
.Os
.Sh NAME
.Nm islower
.Nd lower-case character test
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In ctype.h
.Ft int
.Fn islower "int c"
.Sh DESCRIPTION
The
.Fn islower
function tests for any lower-case letters.
For single C
.Va char Ns s
locales (see
.Xr multibyte 3 )
the value of the argument is
representable as an
.Li unsigned char
or the value of
.Dv EOF .
In the ASCII character set, this includes the following characters
(with their numeric values shown in octal):
.Pp
.Bl -column \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__
.It "\&141\ ``a'' \t142\ ``b'' \t143\ ``c'' \t144\ ``d'' \t145\ ``e''"
.It "\&146\ ``f'' \t147\ ``g'' \t150\ ``h'' \t151\ ``i'' \t152\ ``j''"
.It "\&153\ ``k'' \t154\ ``l'' \t155\ ``m'' \t156\ ``n'' \t157\ ``o''"
.It "\&160\ ``p'' \t161\ ``q'' \t162\ ``r'' \t163\ ``s'' \t164\ ``t''"
.It "\&165\ ``u'' \t166\ ``v'' \t167\ ``w'' \t170\ ``x'' \t171\ ``y''"
.It "\&172\ ``z''"
.El
.Sh RETURN VALUES
The
.Fn islower
function returns zero if the character tests false and
returns non-zero if the character tests true.
.Sh COMPATIBILITY
Although
.Fn islower
accepts arguments outside of the range of the
.Vt "unsigned char"
type in locales with large character sets,
this is a
.Bx 4.4
extension and the
.Fn iswlower
function should be used instead for maximum portability.
.Sh SEE ALSO
.Xr ctype 3 ,
.Xr iswlower 3 ,
.Xr multibyte 3 ,
.Xr tolower 3 ,
.Xr ascii 7
.Sh STANDARDS
The
.Fn islower
function conforms to
.St -isoC .