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NAME
towlower, towlower_l - convert a wide character to lowercase
LIBRARY
Standard C library (libc, -lc)
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 conversion 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 character 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.
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 │
└──────────────────────────────────────────────────────────────────────┴───────────────┴────────────────┘
STANDARDS
towlower()
C11, POSIX.1-2008 (XSI).
towlower_l()
POSIX.1-2008.
STANDARDS
towlower()
C99, POSIX.1-2001 (XSI). Obsolete in POSIX.1-2008 (XSI).
towlower_l()
glibc 2.3. 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 characters, because Unicode knows about
three cases: upper, lower, and title case.
SEE ALSO
iswlower(3), towctrans(3), towupper(3), locale(7)
Linux man-pages 6.7 2023-10-31 towlower(3)