iswalnum(3) Library Functions Manual iswalnum(3)
NAME
iswalnum - test for alphanumeric wide character
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <wctype.h>
int iswalnum(wint_t wc);
DESCRIPTION
The iswalnum() function is the wide-character equivalent of the isal-
num(3) function. It tests whether wc is a wide character belonging to
the wide-character class "alnum".
The wide-character class "alnum" is a subclass of the wide-character
class "graph", and therefore also a subclass of the wide-character
class "print".
Being a subclass of the wide-character class "print", the wide-charac-
ter class "alnum" is disjoint from the wide-character class "cntrl".
Being a subclass of the wide-character class "graph", the wide-charac-
ter class "alnum" is disjoint from the wide-character class "space" and
its subclass "blank".
The wide-character class "alnum" is disjoint from the wide-character
class "punct".
The wide-character class "alnum" is the union of the wide-character
classes "alpha" and "digit". As such, it also contains the wide-char-
acter class "xdigit".
The wide-character class "alnum" always contains at least the letters
'A' to 'Z', 'a' to 'z', and the digits '0' to '9'.
RETURN VALUE
The iswalnum() function returns nonzero if wc is a wide character be-
longing to the wide-character class "alnum". Otherwise, it returns
zero.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌────────────────────────────────────┬───────────────┬────────────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────┼───────────────┼────────────────┤
│ iswalnum() │ Thread safety │ MT-Safe locale │
└────────────────────────────────────┴───────────────┴────────────────┘
STANDARDS
C11, POSIX.1-2008.
HISTORY
POSIX.1-2001, C99.
NOTES
The behavior of iswalnum() depends on the LC_CTYPE category of the cur-
rent locale.
SEE ALSO
isalnum(3), iswctype(3)
Linux man-pages 6.7 2023-10-31 iswalnum(3)
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