57 lines
1.4 KiB
C
57 lines
1.4 KiB
C
/*
|
|
FUNCTION
|
|
<<wcswidth>>---number of column positions of a wide-character string
|
|
|
|
INDEX
|
|
wcswidth
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <wchar.h>
|
|
int wcswidth(const wchar_t *<[pwcs]>, size_t <[n]>);
|
|
|
|
TRAD_SYNOPSIS
|
|
#include <wchar.h>
|
|
int wcswidth(<[pwcs]>, <[n]>)
|
|
wchar_t *<[wc]>;
|
|
size_t <[n]>;
|
|
|
|
DESCRIPTION
|
|
The <<wcswidth>> function shall determine the number of column
|
|
positions required for <[n]> wide-character codes (or fewer than <[n]>
|
|
wide-character codes if a null wide-character code is encountered
|
|
before <[n]> wide-character codes are exhausted) in the string pointed
|
|
to by <[pwcs]>.
|
|
|
|
RETURNS
|
|
The <<wcswidth>> function either shall return 0 (if <[pwcs]> points to a
|
|
null wide-character code), or return the number of column positions
|
|
to be occupied by the wide-character string pointed to by <[pwcs]>, or
|
|
return -1 (if any of the first <[n]> wide-character codes in the
|
|
wide-character string pointed to by <[pwcs]> is not a printable
|
|
wide-character code).
|
|
|
|
PORTABILITY
|
|
<<wcswidth>> has been introduced in the Single UNIX Specification Volume 2.
|
|
<<wcswidth>> has been marked as an extension in the Single UNIX Specification Volume 3.
|
|
*/
|
|
|
|
#include <_ansi.h>
|
|
#include <wchar.h>
|
|
|
|
int
|
|
_DEFUN (wcswidth, (pwcs, n),
|
|
_CONST wchar_t *pwcs _AND
|
|
size_t n)
|
|
|
|
{
|
|
int w, len = 0;
|
|
if (!pwcs || n == 0)
|
|
return 0;
|
|
do {
|
|
if ((w = wcwidth (*pwcs)) < 0)
|
|
return -1;
|
|
len += w;
|
|
} while (*pwcs++ && --n > 0);
|
|
return len;
|
|
}
|