php man page for iswlower

ISWLOWER(3)						     Linux Programmer's Manual						       ISWLOWER(3)

NAME
       iswlower - test for lowercase wide character

SYNOPSIS
       #include <wctype.h>

       int iswlower(wint_t wc);

DESCRIPTION
       The  iswlower() function is the wide-character equivalent of the islower(3) function.  It tests whether wc is a wide character belonging to
       the wide-character class "lower".

       The wide-character class "lower" is a subclass of the wide-character class "alpha", and therefore also a  subclass  of  the  wide-character
       class "alnum", of the wide-character class "graph" and of the wide-character class "print".

       Being a subclass of the wide-character class "print", the wide-character class "lower" is disjoint from the wide-character class "cntrl".

       Being  a  subclass  of the wide-character class "graph", the wide-character class "lower" is disjoint from the wide-character class "space"
       and its subclass "blank".

       Being a subclass of the wide-character class "alnum", the wide-character class "lower" is disjoint from the wide-character class "punct".

       Being a subclass of the wide-character class "alpha", the wide-character class "lower" is disjoint from the wide-character class "digit".

       The wide-character class "lower" contains at least those characters wc which are equal to towlower(wc) and different from towupper(wc).

       The wide-character class "lower" always contains at least the letters 'a' to 'z'.

RETURN VALUE
       The iswlower() function returns nonzero if wc is a wide character belonging to the wide-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 | MT-Safe locale |
       +-----------+---------------+----------------+
CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, 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.

SEE ALSO
       islower(3), iswctype(3), towlower(3)

COLOPHON
       This page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and  the
       latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

GNU
								    2015-08-08							       ISWLOWER(3)