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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).

     allbox; lb lb  lb  l  l  l.   Interface Attribute Value  T{  towlower()
     T}   Thread   safety MT-Safe   locale   T{   towlower_l()   T}   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.