int
wcwidth(
wchar_t wc
)
)
function determines the number of column positions required to
display the wide character
wc
.
)
function returns 0 if the
wc
argument is a nul wide character (L'\0'),
-1 if
wc
is not printable,
otherwise it returns the number of column positions the
character occupies.
wint_t ch;
int column, w;
column = 0;
while ((ch = getwchar()) != WEOF) {
w = wcwidth(ch);
if (w > 0 && column + w >= 20) {
putwchar(L'\n');
column = 0;
}
putwchar(ch);
if (ch == L'\n')
column = 0;
else if (w > 0)
column += w;
}
)
function conforms to
IEEE Std 1003.1-2001 (``POSIX.1'') .