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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 isalnum(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-character class "alnum" is disjoint from the wide-character class "cntrl".

Being a subclass of the wide-character class "graph", the wide-character 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-character 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 belonging to the wide-character class "alnum". Otherwise, it returns zero.

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(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 current locale.

SEE ALSO

isalnum(3), iswctype(3)

2024-05-02 Linux man-pages 6.9.1