'\" t .\" Copyright (c) Bruno Haible .\" .\" SPDX-License-Identifier: GPL-2.0-or-later .\" .\" References consulted: .\" GNU glibc-2 source code and manual .\" Dinkumware C library reference http://www.dinkumware.com/ .\" OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html .\" .TH wcswidth 3 2024-05-02 "Linux man-pages 6.9.1" .SH NAME wcswidth \- determine columns needed for a fixed-size wide-character string .SH LIBRARY Standard C library .RI ( libc ", " \-lc ) .SH SYNOPSIS .nf .BR "#define _XOPEN_SOURCE" " /* See feature_test_macros(7) */" .B #include .P .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 For an explanation of the terms used in this section, see .BR attributes (7). .TS allbox; lbx lb lb l l l. Interface Attribute Value T{ .na .nh .BR wcswidth () T} Thread safety MT-Safe locale .TE .SH STANDARDS POSIX.1-2008. .SH HISTORY 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)