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

       iswctype, iswctype_l — test character for a specified class

SYNOPSIS

       #include <wctype.h>

       int iswctype(wint_t wc, wctype_t charclass);
       int iswctype_l(wint_t wc, wctype_t charclass,
           locale_t locale);

DESCRIPTION

       For  iswctype():  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.1‐2008 defers to the ISO C standard.

       The  iswctype() and iswctype_l() functions shall determine whether the wide-character code
       wc has the character  class  charclass,  returning  true  or  false.  The  iswctype()  and
       iswctype_l()  functions  are defined on WEOF and wide-character codes corresponding to the
       valid character encodings in the current locale, or in the locale represented  by  locale,
       respectively.  If  the  wc  argument  is  not in the domain of the function, the result is
       undefined.  If the value of charclass is invalid (that is,  not  obtained  by  a  call  to
       wctype() or charclass is invalidated by a subsequent call to setlocale() that has affected
       category LC_CTYPE) the result is unspecified.

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

RETURN VALUE

       The  iswctype()  and iswctype_l() functions shall return non-zero (true) if and only if wc
       has the property described by charclass.  If charclass is 0, these functions shall  return
       0.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

   Testing for a Valid Character
           #include <wctype.h>
           ...
           int yes_or_no;
           wint_t wc;
           wctype_t valid_class;
           ...
           if ((valid_class=wctype("vowel")) == (wctype_t)0)
               /* Invalid character class. */
           yes_or_no=iswctype(wc,valid_class);

APPLICATION USAGE

       The twelve strings "alnum", "alpha", "blank", "cntrl", "digit", "graph", "lower", "print",
       "punct", "space", "upper", and "xdigit" are reserved for the standard  character  classes.
       In  the  table  below, the functions in the left column are equivalent to the functions in
       the right column.

           iswalnum(wc)            iswctype(wc, wctype("alnum"))
           iswalnum_l(wc, locale)  iswctype_l(wc, wctype("alnum"), locale)
           iswalpha(wc)            iswctype(wc, wctype("alpha"))
           iswalpha_l(wc, locale)  iswctype_l(wc, wctype("alpha"), locale)
           iswblank(wc)            iswctype(wc, wctype("blank"))
           iswblank_l(wc, locale)  iswctype_l(wc, wctype("blank"), locale)
           iswcntrl(wc)            iswctype(wc, wctype("cntrl"))
           iswcntrl_l(wc, locale)  iswctype_l(wc, wctype("cntrl"), locale)
           iswdigit(wc)            iswctype(wc, wctype("digit"))
           iswdigit_l(wc, locale)  iswctype_l(wc, wctype("digit"), locale)
           iswgraph(wc)            iswctype(wc, wctype("graph"))
           iswgraph_l(wc, locale)  iswctype_l(wc, wctype("graph"), locale)
           iswlower(wc)            iswctype(wc, wctype("lower"))
           iswlower_l(wc, locale)  iswctype_l(wc, wctype("lower"), locale)
           iswprint(wc)            iswctype(wc, wctype("print"))
           iswprint_l(wc, locale)  iswctype_l(wc, wctype("print"), locale)
           iswpunct(wc)            iswctype(wc, wctype("punct"))
           iswpunct_l(wc, locale)  iswctype_l(wc, wctype("punct"), locale)
           iswspace(wc)            iswctype(wc, wctype("space"))
           iswspace_l(wc, locale)  iswctype_l(wc, wctype("space"), locale)
           iswupper(wc)            iswctype(wc, wctype("upper"))
           iswupper_l(wc, locale)  iswctype_l(wc, wctype("upper"), locale)
           iswxdigit(wc)           iswctype(wc, wctype("xdigit"))
           iswxdigit_l(wc, locale) iswctype_l(wc, wctype("xdigit"), locale)

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       iswalnum(),  iswalpha(),  iswcntrl(),  iswdigit(),  iswgraph(),  iswlower(),   iswprint(),
       iswpunct(), iswspace(), iswupper(), iswxdigit(), setlocale(), uselocale(), wctype()

       The Base Definitions volume of POSIX.1‐2008, <locale.h>, <wctype.h>

COPYRIGHT

       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1, 2013 Edition, Standard for Information Technology  --  Portable  Operating  System
       Interface  (POSIX),  The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical  Corrigendum  1  applied.)  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.unix.org/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 .