преобразовать широкий символ в нижний регистр (convert a wide character to lowercase)
Имя (Name)
towlower, towlower_l - convert a wide character to lowercase
Синопсис (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
Описание (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.
Возвращаемое значение (Return value)
If wc was convertible to lowercase, towlower() returns its
lowercase equivalent; otherwise it returns wc.
Версии (Versions)
The towlower_l() function first appeared in glibc 2.3.
Атрибуты (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 │
└───────────────────────────────┴───────────────┴────────────────┘
Стандарты (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.
Примечание (Note)
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.
Смотри также (See also)
iswlower(3), towctrans(3), towupper(3), locale(7)
