.\"	$OpenBSD: towlower.3,v 1.6 2017/09/05 03:16:13 schwarze Exp $
.\"	$NetBSD: towlower.3,v 1.7 2003/09/08 17:54:31 wiz Exp $
.\"
.\" Copyright (c) 1989, 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\"
.\"	@(#)tolower.3	5.2 (Berkeley) 6/29/91
.\"
.Dd $Mdocdate: September 5 2017 $
.Dt TOWLOWER 3
.Os
.Sh NAME
.Nm towlower ,
.Nm towlower_l ,
.Nm towupper ,
.Nm towupper_l
.Nd wide-character case letter conversion utilities
.Sh SYNOPSIS
.In wctype.h
.Ft wint_t
.Fn towlower "wint_t wc"
.Ft wint_t
.Fn towlower_l "wint_t wc" "locale_t locale"
.Ft wint_t
.Fn towupper "wint_t wc"
.Ft wint_t
.Fn towupper_l "wint_t wc" "locale_t locale"
.Sh DESCRIPTION
The
.Fn towlower
and
.Fn towlower_l
functions convert an upper-case wide character
to the corresponding lower-case letter.
The
.Fn towupper
and
.Fn towupper_l
functions convert a lower-case wide character
to the corresponding upper-case letter.
.Pp
The functions
.Fn towlower_l
and
.Fn towupper_l
use the specified
.Fa locale ,
whereas
.Fn towlower
and
.Fn towupper
use the thread-specific locale set with
.Xr uselocale 3 ,
falling back to the global locale set with
.Xr setlocale 3 .
.Sh RETURN VALUES
These functions return the corresponding character, if any.
Otherwise,
.Fa wc
is returned unchanged.
.Sh SEE ALSO
.Xr iswlower 3 ,
.Xr tolower 3 ,
.Xr toupper 3 ,
.Xr towctrans 3
.Sh STANDARDS
The functions
.Fn towlower
and
.Fn towupper
conform to
.St -isoC-amd1
and
.St -isoC-99 ,
and
.Fn towlower_l
and
.Fn towupper_l
to
.St -p1003.1-2008 .
.Sh HISTORY
The functions
.Fn towlower
and
.Fn towupper
have been available since
.Ox 3.8 ,
and
.Fn towlower_l
and
.Fn towupper_l
since
.Ox 6.2 .