.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
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.\" References consulted:
.\"   GNU glibc-2 source code and manual
.\"   Dinkumware C library reference http://www.dinkumware.com/
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.TH WCSWIDTH 3  2014-01-22 "GNU" "Linux Programmer's Manual"
.SH NAME
wcswidth \- determine columns needed for a fixed-size wide-character string
.SH SYNOPSIS
.nf
.BR "#define _XOPEN_SOURCE" "             /* See feature_test_macros(7) */"
.B #include <wchar.h>
.sp
.BI "int wcswidth(const wchar_t *" s ", size_t " n );
.fi
.SH DESCRIPTION
The
.BR wcswidth ()
function returns the
number of columns needed to represent
the wide-character string pointed to by
.IR s ,
but at most
.I n
wide
characters.
If a nonprintable wide character occurs among these characters,
\-1 is returned.
.SH RETURN VALUE
The
.BR wcswidth ()
function
returns the number of column positions for the
wide-character string
.IR s ,
truncated to at most length
.IR n .
.SH ATTRIBUTES
.SS Multithreading (see pthreads(7))
The
.BR wcswidth ()
function is thread-safe with exceptions.
It can be safely used in multithreaded applications, as long as
.BR setlocale (3)
is not called to change the locale during its execution.
.SH CONFORMING TO
POSIX.1-2001.
.SH NOTES
The behavior of
.BR wcswidth ()
depends on the
.B LC_CTYPE
category of the
current locale.
.SH SEE ALSO
.BR iswprint (3),
.BR wcwidth (3)
.SH COLOPHON
This page is part of release 3.79 of the Linux
.I man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
\%http://www.kernel.org/doc/man\-pages/.