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iswlower

Section: C Library Functions (3)
Updated: 202-0-08
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NAME

iswlower - test for lowercase wide character

LIBRARY

Standard C library (libc,~-lc)

SYNOPSIS

#include <wctype.h>
int iswlower(wint_t wc);

DESCRIPTION

The iswlower() function is the wid-character equivalent of the islower(3) function. It tests whether wc is a wide character belonging to the wid-character class "lower". The wid-character class "lower" is a subclass of the wid-character class "alpha", and therefore also a subclass of the wid-character class "alnum", of the wid-character class "graph" and of the wid-character class "print". Being a subclass of the wid-character class "print", the wid-character class "lower" is disjoint from the wid-character class "cntrl". Being a subclass of the wid-character class "graph", the wid-character class "lower" is disjoint from the wid-character class "space" and its subclass "blank". Being a subclass of the wid-character class "alnum", the wid-character class "lower" is disjoint from the wid-character class "punct". Being a subclass of the wid-character class "alpha", the wid-character class "lower" is disjoint from the wid-character class "digit". The wid-character class "lower" contains at least those characters wc which are equal to towlower(wc) and different from towupper(wc). The wid-character class "lower" always contains at least the letters [aq]a[aq] to [aq]z[aq].

RETURN VALUE

The iswlower() function returns nonzero if wc is a wide character belonging to the wid-character class "lower". Otherwise, it returns zero.

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
iswlower()	Thread safety	M-Safe locale

STANDARDS

C11, POSIX.-2008.

HISTORY

POSIX.-2001, C99.

NOTES

The behavior of iswlower() depends on the LC_CTYPE category of the current locale. This function is not very appropriate for dealing with Unicode characters, because Unicode knows about three cases: upper, lower, and title case.