PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

NAME

       towlower, towlower_l — transliterate uppercase wide-character code to lowercase

SYNOPSIS

       #include <wctype.h>

       wint_t towlower(wint_t wc);
       wint_t towlower_l(wint_t wc, locale_t locale);

DESCRIPTION

       For  towlower():  The  functionality  described on this reference page is aligned with the
       ISO C standard. Any conflict  between  the  requirements  described  here  and  the  ISO C
       standard is unintentional. This volume of POSIX.1‐2017 defers to the ISO C standard.

       The  towlower()  and  towlower_l()  functions have as a domain a type wint_t, the value of
       which the application shall ensure is a character representable as a wchar_t, and a  wide-
       character  code  corresponding  to a valid character in the locale used by the function or
       the value of WEOF.  If the argument has any other value, the behavior  is  undefined.   If
       the  argument  of  towlower() or towlower_l() represents an uppercase wide-character code,
       and there exists a corresponding lowercase wide-character code  as  defined  by  character
       type  information  in  the  current  locale  or  in  the  locale  represented  by  locale,
       respectively (category LC_CTYPE), the result shall be the  corresponding  lowercase  wide-
       character code.  All other arguments in the domain are returned unchanged.

       The  behavior  is  undefined  if the locale argument to towlower_l() is the special locale
       object LC_GLOBAL_LOCALE or is not a valid locale object handle.

RETURN VALUE

       Upon successful completion, the towlower() and towlower_l()  functions  shall  return  the
       lowercase  letter  corresponding  to the argument passed; otherwise, they shall return the
       argument unchanged.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       setlocale(), uselocale()

       The Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale, <locale.h>, <wctype.h>

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1-2017,  Standard  for  Information Technology -- Portable Operating System Interface
       (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C)  2018  by
       the  Institute  of  Electrical  and Electronics Engineers, Inc and The Open Group.  In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard,  the  original  IEEE  and  The  Open Group Standard is the referee document. The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .