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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-character 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 current locale.
SEE ALSO
isblank(3), iswctype(3)
COLOPHON
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GNU 2019-03-06 ISWBLANK(3)