.\" Copyright (c) 2002 Tim J. Robbins
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.\" $FreeBSD: head/lib/libc/string/wcswidth.3 107706 2002-12-09 14:04:05Z ru $
.\"
.Dd December 27, 2013
.Dt WCSWIDTH 3
.Os
.Sh NAME
.Nm wcswidth ,
.Nm wcswidth_l
.Nd "number of column positions in wide-character string"
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In wchar.h
.Ft int
.Fn wcswidth "const wchar_t *pwcs" "size_t n"
.In xlocale.h
.Ft int
.Fn wcswidth_l "const wchar_t *pwcs" "size_t n" "locale_t locale"
.Sh DESCRIPTION
The
.Fn wcswidth
and
.Fn wcswidth_l
functions determine the number of column positions required for the first
.Fa n
characters of
.Fa pwcs ,
or until a null wide character (L'\e0') is encountered.
.Pp
The
.Fn wcswidth_l
function takes an explicit
.Fa locale
argument, whereas the
.Fn wcswidth
function uses the current global or per-thread locale.
.Sh RETURN VALUES
The
.Fn wcswidth
and
.Fn wcswidth_l
functions return 0 if
.Fa pwcs
is an empty string (L""),
\-1 if a non-printing wide character is encountered,
otherwise they return the number of column positions occupied.
.Sh SEE ALSO
.Xr iswprint 3 ,
.Xr wcwidth 3 ,
.Xr xlocale 3
.Sh STANDARDS
The
.Fn wcswidth
function conforms to
.St -p1003.1-2001 .