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iswalnum

Section: C Library Functions (3)
Updated: 202-0-08
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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 wid-character equivalent of the isalnum(3) function. It tests whether wc is a wide character belonging to the wid-character class "alnum". The wid-character class "alnum" is a subclass of the wid-character class "graph", and therefore also a subclass of the wid-character class "print". Being a subclass of the wid-character class "print", the wid-character class "alnum" is disjoint from the wid-character class "cntrl". Being a subclass of the wid-character class "graph", the wid-character class "alnum" is disjoint from the wid-character class "space" and its subclass "blank". The wid-character class "alnum" is disjoint from the wid-character class "punct". The wid-character class "alnum" is the union of the wid-character classes "alpha" and "digit". As such, it also contains the wid-character class "xdigit". The wid-character class "alnum" always contains at least the letters [aq]A[aq] to [aq]Z[aq], [aq]a[aq] to [aq]z[aq], and the digits [aq]0[aq] to [aq]9[aq].

RETURN VALUE

The iswalnum() function returns nonzero if wc is a wide character belonging to the wid-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	M-Safe locale

STANDARDS

C11, POSIX.-2008.

HISTORY

POSIX.-2001, C99.

NOTES

The behavior of iswalnum() depends on the LC_CTYPE category of the current locale.