iswblank(3) Library Functions Manual iswblank(3)
NAME
iswblank - test for whitespace wide character
LIBRARY
Standard C library (libc, -lc)
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 is-
blank(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 be-
longing to the wide-character class "blank". Otherwise, it returns
zero.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌────────────────────────────────────┬───────────────┬────────────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────┼───────────────┼────────────────┤
│ iswblank() │ Thread safety │ MT-Safe locale │
└────────────────────────────────────┴───────────────┴────────────────┘
STANDARDS
POSIX.1-2008.
HISTORY
POSIX.1-2001.
NOTES
The behavior of iswblank() depends on the LC_CTYPE category of the cur-
rent locale.
SEE ALSO
isblank(3), iswctype(3)
Linux man-pages 6.7 2023-10-31 iswblank(3)
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