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/*

FUNCTION

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

INDEX

        wcwidth

ANSI_SYNOPSIS

        #include <wchar.h>

        int wcwidth(const wchar_t <[wc]>);

TRAD_SYNOPSIS

        #include <wchar.h>

        int wcwidth(<[wc]>)

        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.

RETURNS

        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).

        The current implementation of <<wcwidth>> simply sets the width

        of all printable characters to 1 since newlib has no character

        tables around.

PORTABILITY

<<wcwidth>> has been introduced in the Single UNIX Specification Volume 2.

<<wcwidth>> has been marked as an extension in the Single UNIX Specification Volume 3.

*/

#include <_ansi.h>

#include <wchar.h>

#include <wctype.h>

int

_DEFUN (wcwidth, (wc),

        _CONST wchar_t wc)

{

  if (iswprint (wc))

    return 1;

  if (iswcntrl (wc) || wc == L'\0')

    return 0;

  return -1;

}