def make_break(lineno, p):
    """ Checks if --enable-break is set, and if so, calls
    BREAK keyboard interruption for this line if it has not been already
    checked """
    global last_brk_linenum

    if not OPTIONS.enableBreak.value or lineno == last_brk_linenum or is_null(p):
        return None

    last_brk_linenum = lineno
    return make_sentence('CHKBREAK', make_number(lineno, lineno, TYPE.uinteger))