s/nonnegative/non-negative/

[thirdparty/man-pages.git] / man3 / iswlower.3

.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
.\"
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.\" modify it under the terms of the GNU General Public License as
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.\" References consulted:
.\"   GNU glibc-2 source code and manual
.\"   Dinkumware C library reference http://www.dinkumware.com/
.\"   OpenGroup's Single Unix specification http://www.UNIX-systems.org/online.html
.\"   ISO/IEC 9899:1999
.\"
.TH ISWLOWER 3  1999-07-25 "GNU" "Linux Programmer's Manual"
.SH NAME
iswlower \- test for lowercase wide character
.SH SYNOPSIS
.nf
.B #include <wctype.h>
.sp
.BI "int iswlower(wint_t " wc );
.fi
.SH DESCRIPTION
The \fBiswlower\fP() function is the wide-character equivalent of the
\fBislower\fP() function.
It tests whether \fIwc\fP is a wide character
belonging to the wide character class "lower".
.PP
The wide character class "lower" is a subclass of the wide character class
"alpha", and therefore also a subclass 
of the wide character class "alnum", of
the wide character class "graph" and of the wide character class "print".
.PP
Being a subclass of the wide character class "print",
the wide character class
"lower" is disjoint from the wide character class "cntrl".
.PP
Being a subclass of the wide character class "graph",
the wide character class "lower" is disjoint from the 
wide character class "space" and its subclass "blank".
.PP
Being a subclass of the wide character class "alnum",
the wide character class
"lower" is disjoint from the wide character class "punct".
.PP
Being a subclass of the wide character class "alpha",
the wide character class
"lower" is disjoint from the wide character class "digit".
.PP
The wide character class "lower" contains at least
those characters \fIwc\fP
which are equal to \fItowlower(wc)\fP and different
from \fItowupper(wc)\fP.
.PP
The wide character class "lower" always contains
at least the letters 'a'
to 'z'.
.SH "RETURN VALUE"
The \fBiswlower\fP() function returns non-zero
if \fIwc\fP is a wide character
belonging to the wide character class "lower".
Otherwise it returns zero.
.SH "CONFORMING TO"
C99.
.SH "SEE ALSO"
.BR islower (3),
.BR iswctype (3),
.BR towlower (3)
.SH NOTES
The behaviour of \fBiswlower\fP() depends on the LC_CTYPE category of the
current locale.
.PP
This function is not very appropriate for dealing with Unicode characters,
because Unicode knows about three cases: upper, lower and title case.