iswblank

       #include <wctype.h>

       int iswblank(wint_t wc);

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

       iswblank():
              _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
              _POSIX_C_SOURCE >= 200112L;
              or cc -std=c99

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.

SEE ALSO
       isblank(3), iswctype(3)

COLOPHON
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