Linux manual pages Section 3  

Name

wcwidth — determine columns needed for a wide character

Synopsis

#define _XOPEN_SOURCE        /* See feature_test_macros(7) */
#include <wchar.h>
int wcwidth( wchar_t c);
 

DESCRIPTION

The wcwidth() function returns the number of columns needed to represent the wide character c. If c is a printable wide character, the value is at least 0. If c is null wide character (L'\0'), the value is 0. Otherwise, −1 is returned.

RETURN VALUE

The wcwidth() function returns the number of column positions for c.

ATTRIBUTES

Multithreading (see pthreads(7))

The wcwidth() function is thread-safe with exceptions. It can be safely used in multithreaded applications, as long as setlocale(3) is not called to change the locale during its execution.

CONFORMING TO

POSIX.1-2001.

Note that glibc before 2.2.5 used the prototype

  int wcwidth(wint_t c);

NOTES

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

SEE ALSO

iswprint(3), wcswidth(3)

COLOPHON

This page is part of release 3.72 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 http://www.kernel.org/doc/man−pages/.


  Copyright (c) Bruno Haible <haibleclisp.cons.org>

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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