TOWLOWER(3) Linux Programmer's Manual TOWLOWER(3)
NAME
towlower, towlower_l - convert a wide character to lowercase
SYNOPSIS
#include <wctype.h>
wint_t towlower(wint_t wc);
wint_t towlower_l(wint_t wc, locale_t locale);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
towlower_l():
Since glibc 2.10:
_XOPEN_SOURCE >= 700
Before glibc 2.10:
_GNU_SOURCE
DESCRIPTION
The towlower() function is the wide-character equivalent of the
tolower(3) function. If wc is an uppercase wide character, and there
exists a lowercase equivalent in the current locale, it returns the
lowercase equivalent of wc. In all other cases, wc is returned
unchanged.
The towlower_l() function performs the same task, but performs the con-
version based on the character type information in the locale specified
by locale. The behavior of towlower_l() is undefined if locale is the
special locale object LC_GLOBAL_LOCALE (see duplocale(3)) or is not a
valid locale object handle.
The argument wc must be representable as a wchar_t and be a valid char-
acter in the locale or be the value WEOF.
RETURN VALUE
If wc was convertible to lowercase, towlower() returns its lowercase
equivalent; otherwise it returns wc.
VERSIONS
The towlower_l() function first appeared in glibc 2.3.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
+-------------+---------------+----------------+
|Interface | Attribute | Value |
+-------------+---------------+----------------+
|towlower() | Thread safety | MT-Safe locale |
+-------------+---------------+----------------+
|towlower_l() | Thread safety | MT-Safe |
+-------------+---------------+----------------+
CONFORMING TO
towlower(): C99, POSIX.1-2001 (XSI); present as an XSI extension in
POSIX.1-2008, but marked obsolete.
towlower_l(): POSIX.1-2008.
NOTES
The behavior of these functions depends on the LC_CTYPE category of the
locale.
These functions are not very appropriate for dealing with Unicode char-
acters, because Unicode knows about three cases: upper, lower and title
case.
SEE ALSO
iswlower(3), towctrans(3), towupper(3), locale(7)
COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
GNU 2017-09-15 TOWLOWER(3)