Reopens the stdout and stderr output files, as set by
    L{outputToFiles}.

def reopenOutputFiles():
    """
    Reopens the stdout and stderr output files, as set by
    L{outputToFiles}.
    """
    if not _stdout and not _stderr:
        debug('log', 'told to reopen log files, but log files not set')
        return

    def reopen(name, fileno, *args):
        oldmask = os.umask(0026)
        try:
            f = open(name, 'a+', *args)
        finally:
            os.umask(oldmask)

        os.dup2(f.fileno(), fileno)

    if _stdout:
        reopen(_stdout, sys.stdout.fileno())

    if _stderr:
        reopen(_stderr, sys.stderr.fileno(), 0)
        debug('log', 'opened log %r', _stderr)