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ISWBLANK(3) Linux Programmer's Manual ISWBLANK(3)

NAME

     iswblank - test for whitespace wide character

SYNOPSIS

     #include <wctype.h>

     int iswblank(wint_t wc);

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

     iswblank():
            _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

DESCRIPTION

     The  iswblank()  function  is  the  wide-character  equivalent  of  the
     isblank(3) function.  It tests whether wc is a wide character belonging
     to the wide-character class "blank".

     The  wide-character  class  "blank" is a subclass of the wide-character
     class "space".

     Being a subclass of the wide-character class "space", the  wide-charac-
     ter class "blank" is disjoint from the wide-character class "graph" and
     therefore also disjoint from its subclasses "alnum", "alpha",  "upper",
     "lower", "digit", "xdigit", "punct".

     The  wide-character  class  "blank"  always contains at least the space
     character and the control character '\t'.

RETURN VALUE

     The iswblank() function returns nonzero  if  wc  is  a  wide  character
     belonging  to  the wide-character class "blank".  Otherwise, it returns
     zero.

ATTRIBUTES

     For  an  explanation  of  the  terms  used   in   this   section,   see
     attributes(7).

     +-----------+---------------+----------------+
     |Interface  | Attribute     | Value          |
     +-----------+---------------+----------------+
     |iswblank() | Thread safety | MT-Safe locale |
     +-----------+---------------+----------------+

CONFORMING TO

     POSIX.1-2001, POSIX.1-2008.

NOTES

     The behavior of iswblank() depends on the LC_CTYPE category of the cur-
     rent locale.