{
    /*
     * If the character is within the first 127 characters, just use the
     * standard C function, otherwise consult the Unicode table.
     */

    if (((Tcl_UniChar) ch) < ((Tcl_UniChar) 0x80)) {
	return isspace(UCHAR(ch)); /* INTL: ISO space */
    } else if ((Tcl_UniChar) ch == 0x0085 || (Tcl_UniChar) ch == 0x180e
	    || (Tcl_UniChar) ch == 0x200b || (Tcl_UniChar) ch == 0x2060
	    || (Tcl_UniChar) ch == 0xfeff) {
	return 1;
    } else {
	return ((SPACE_BITS >> GetCategory(ch)) & 1);
    }