portalocker - Cross-platform locking library

Overview

Portalocker is a library to provide an easy API to file locking.

Originally created as a Python Recipe by Jonathan Feinberg and Lowell Alleman http://code.activestate.com/recipes/65203-portalocker-cross-platform-posixnt-api-for-flock-s/

The module is currently maintained by Rick van Hattem <Wolph@wol.ph>. The project resides at https://github.com/WoLpH/portalocker . Bugs and feature requests can be submitted there. Patches are also very welcome.

Links

• Documentation

  • http://portalocker.readthedocs.org/en/latest/

• Source

  • https://github.com/WoLpH/portalocker

• Bug reports

  • https://github.com/WoLpH/portalocker/issues

• Package homepage

  • https://pypi.python.org/pypi/portalocker

• My blog

  • http://w.wol.ph/

Examples

To make sure your cache generation scripts don't race, use the Lock class:

>>> import portalocker
>>> with portalocker.Lock('somefile', timeout=1) as fh:
    print >>fh, 'writing some stuff to my cache...'

To customize the opening and locking a manual approach is also possible:

>>> import portalocker
>>> file = open('somefile', 'r+')
>>> portalocker.lock(file, portalocker.LOCK_EX)
>>> file.seek(12)
>>> file.write('foo')
>>> file.close()

There is no explicit need to unlock the file as it is automatically unlocked after file.close(). If you still feel the need to manually unlock a file than you can do it like this:

>>> portalocker.unlock(file)

Do note that your data might still be in a buffer so it is possible that your data is not available until you flush() or close().

Changelog

See CHANGELOG file

License

see the LICENSE file