Manpages - towlower.3

towlower, towlower_l - convert a wide character to lowercase

  #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

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.

If wc was convertible to lowercase, *towlower*() returns its lowercase equivalent; otherwise it returns wc.

The *towlower_l*() function first appeared in glibc 2.3.

For an explanation of the terms used in this section, see *attributes*(7).

*towlower*(): C99, POSIX.1-2001 (XSI); present as an XSI extension in POSIX.1-2008, but marked obsolete.

*towlower_l*(): POSIX.1-2008.

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.

*iswlower*(3), *towctrans*(3), *towupper*(3), *locale*(7)

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