onion.py 文件源码

def is_tor_data_dir_usable(tor_data_dir):
    """
    Checks if the Tor data dir specified is usable. This means that
     it is not being locked and we have permissions to write to it.
    """
    if not os.path.exists(tor_data_dir):
        return True

    try:
        fcntl.flock(open(os.path.join(tor_data_dir, 'lock'), 'w'),
                    fcntl.LOCK_EX | fcntl.LOCK_NB)
        return True
    except (IOError, OSError) as err:
        if err.errno == errno.EACCES:
            # Permission error
            return False
        elif err.errno == errno.EAGAIN:
            # File locked
            return False