Source code for volttron.platform.lib.inotify.green

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'''gevent-safe interface to Linux inotify system calls.'''

import errno as errno
import sys

import gevent
from gevent.select import select

from . import _inotify, __all__, _main
from . import *
import logging

_log = logging.getLogger(__name__)


[docs]class inotify(_inotify): class _lock_class(object): def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): pass def __init__(self, flags=0): try: super(inotify, self).__init__(flags | IN_NONBLOCK) except Exception as e: # Could happen due to I/O errors. Example - too many open files _log.error("Error instantiating inotify. " "Auth files will not be monitored for updates. Exception: {}".format(e)) raise e
[docs] def read(self): while True: try: return super(inotify, self).read() except OSError as exc: if exc.errno != errno.EAGAIN: raise select([self], [], [])
if __name__ == '__main__': try: gevent.spawn(_main, sys.argv, inotify).join() except KeyboardInterrupt: pass