towupper, towupper_l - convert a wide character to uppercase


   #include <wctype.h>

   wint_t towupper(wint_t wc);

   wint_t towupper_l(wint_t wc, locale_t locale);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       Since glibc 2.10:
              _XOPEN_SOURCE >= 700
       Before glibc 2.10:


   The  towupper()  function  is  the  wide-character  equivalent  of  the
   toupper(3) function.  If wc is a lowercase wide  character,  and  there
   exists  an  uppercase  equivalent in the current locale, it returns the
   uppercase equivalent of  wc.   In  all  other  cases,  wc  is  returned

   The  towupper_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 towupper_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 uppercase, towupper()  returns  its  uppercase
   equivalent; otherwise it returns wc.


   The towupper_l() function first appeared in glibc 2.3.


   For   an   explanation   of   the  terms  used  in  this  section,  see

   Interface     Attribute      Value          
   towupper()    Thread safety  MT-Safe locale 
   towupper_l()  Thread safety  MT-Safe        


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

   towupper_l(): POSIX.1-2008.


   The behavior of these functions depends on the LC_CTYPE category of the

   These functions are not  very  appropriate  for  dealing  with  Unicode
   characters,  because  Unicode knows about three cases: upper, lower and
   title case.


   iswupper(3), towctrans(3), towlower(3), locale(7)


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   description  of  the project, information about reporting bugs, and the
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