wcswidth—number of column positions of a wide-character string #include <wchar.h>
int wcswidth(const wchar_t *pwcs, 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.