iswalpha(3) Library Functions Manual iswalpha(3)
NAME
iswalpha - test for alphabetic wide character
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <wctype.h>
int iswalpha(wint_t wc);
DESCRIPTION
The iswalpha() function is the wide-character equivalent of the isal-
pha(3) function. It tests whether wc is a wide character belonging to
the wide-character class "alpha".
The wide-character class "alpha" is a subclass of the wide-character
class "alnum", and therefore also a subclass of the wide-character
class "graph" and of the wide-character class "print".
Being a subclass of the wide-character class "print", the wide-charac-
ter class "alpha" is disjoint from the wide-character class "cntrl".
Being a subclass of the wide-character class "graph", the wide-charac-
ter class "alpha" is disjoint from the wide-character class "space" and
its subclass "blank".
Being a subclass of the wide-character class "alnum", the wide-charac-
ter class "alpha" is disjoint from the wide-character class "punct".
The wide-character class "alpha" is disjoint from the wide-character
class "digit".
The wide-character class "alpha" contains the wide-character classes
"upper" and "lower".
The wide-character class "alpha" always contains at least the letters
'A' to 'Z' and 'a' to 'z'.
RETURN VALUE
The iswalpha() function returns nonzero if wc is a wide character be-
longing to the wide-character class "alpha". Otherwise, it returns
zero.
ATTRIBUTES
For an explanation of the terms used in this section, see at-
tributes(7).
┌─────────────────────────────────────┬───────────────┬────────────────┐
│Interface │ Attribute │ Value │
├─────────────────────────────────────┼───────────────┼────────────────┤
│iswalpha() │ Thread safety │ MT-Safe locale │
└─────────────────────────────────────┴───────────────┴────────────────┘
STANDARDS
POSIX.1-2001, POSIX.1-2008, C99.
NOTES
The behavior of iswalpha() depends on the LC_CTYPE category of the cur-
rent locale.
SEE ALSO
isalpha(3), iswctype(3)
Linux man-pages 6.03 2023-02-05 iswalpha(3)
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