wcwidth (3p) - Linux Manuals

wcwidth: number of column positions of a wide-character code

PROLOG

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

wcwidth - number of column positions of a wide-character code

SYNOPSIS

#include <wchar.h>

int wcwidth(wchar_t wc);

DESCRIPTION

The wcwidth() function shall determine the number of column positions required for the wide character wc. The application shall ensure that the value of wc is a character representable as a wchar_t, and is a wide-character code corresponding to a valid character in the current locale.

RETURN VALUE

The wcwidth() function shall either return 0 (if wc is a null wide-character code), or return the number of column positions to be occupied by the wide-character code wc, or return -1 (if wc does not correspond to a printable wide-character code).

ERRORS

No errors are defined.

The following sections are informative.

EXAMPLES

None.

APPLICATION USAGE

This function was removed from the final ISO/IEC 9899:1990/Amendment 1:1995 (E), and the return value for a non-printable wide character is not specified.

RATIONALE

None.

FUTURE DIRECTIONS

None.

COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

SEE ALSO

wcswidth(), the Base Definitions volume of IEEE Std 1003.1-2001, <wchar.h>