iswctype(3p) — Linux manual page


ISWCTYPE(3P)            POSIX Programmer's Manual           ISWCTYPE(3P)

PROLOG         top

       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         top

       iswctype, iswctype_l — test character for a specified class

SYNOPSIS         top

       #include <wctype.h>

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

DESCRIPTION         top

       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.1‐2017 defers to the ISO C

       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         top

       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 (wctype_t)0, these functions shall return 0.

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top

   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. */


       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         top




SEE ALSO         top

       iswalnum(3p), iswalpha(3p), iswcntrl(3p), iswdigit(3p),
       iswgraph(3p), iswlower(3p), iswprint(3p), iswpunct(3p),
       iswspace(3p), iswupper(3p), iswxdigit(3p), setlocale(3p),
       uselocale(3p), wctype(3p)

       The Base Definitions volume of POSIX.1‐2017, locale.h(0p),

COPYRIGHT         top

       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 .

       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 .

IEEE/The Open Group               2017                      ISWCTYPE(3P)

Pages that refer to this page: wchar.h(0p)wctype.h(0p)iswalnum(3p)iswalpha(3p)iswblank(3p)iswcntrl(3p)iswdigit(3p)iswgraph(3p)iswlower(3p)iswprint(3p)iswpunct(3p)iswspace(3p)iswupper(3p)iswxdigit(3p)setlocale(3p)wctype(3p)