NAME
wcwidth — number
of column positions of a wide-character code
SYNOPSIS
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.
EXAMPLES
None.
APPLICATION USAGE
This function was removed from the final ISO/IEC 9899/AMD1:1995 (“ISO C90, Amendment 1”) (E), and the return value for a non-printable wide character is not specified.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
XBD <wchar.h>
CHANGE HISTORY
First released as a World-wide Portability Interface in Issue 4. Derived from the MSE working draft.
Issue 6
The Open Group Corrigendum U021/12 is applied. This function is marked as an extension.
The normative text is updated to avoid use of the term "must" for application requirements.