php man page for wcswidth

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

NAME
       wcswidth - determine columns needed for a fixed-size wide-character string

SYNOPSIS
       #define _XOPEN_SOURCE		 /* See feature_test_macros(7) */
       #include <wchar.h>

       int wcswidth(const wchar_t *s, size_t n);

DESCRIPTION
       The  wcswidth()	function  returns  the number of columns needed to represent the wide-character string pointed to by s, but at most n wide
       characters.  If a nonprintable wide character occurs among these characters, -1 is returned.

RETURN VALUE
       The wcswidth() function returns the number of column positions for the wide-character string s, truncated to at most length n.

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

       +-----------+---------------+----------------+
       |Interface  | Attribute	   | Value	    |
       +-----------+---------------+----------------+
       |wcswidth() | Thread safety | MT-Safe locale |
       +-----------+---------------+----------------+
CONFORMING TO
       POSIX.1-2001, POSIX.1-2008.

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

SEE ALSO
       iswprint(3), wcwidth(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							       WCSWIDTH(3)