stouputils.lock package#

Inter-process locks implementing First-In-First-Out (FIFO).

Source: - https://en.wikipedia.org/wiki/File_locking - https://en.wikipedia.org/wiki/Starvation_%28computer_science%29 - https://en.wikipedia.org/wiki/FIFO_and_LIFO_accounting

Provides three classes:

  • LockFifo: basic cross-process lock using filesystem (POSIX via fcntl, Windows via msvcrt).

  • RLockFifo: reentrant per-(process,thread) lock built on top of LockFifo.

  • RedisLockFifo: distributed lock using redis (optional dependency).

Usage#

>>> import stouputils as stp
>>> with stp.LockFifo("some_directory/my.lock", timeout=5):
...     pass

>>> with stp.RLockFifo("some_directory/my_r.lock", timeout=5):
...     pass

>>> def _redis_example():
...     with stp.RedisLockFifo("my_redis_lock", timeout=5):
...         pass
>>> import os
>>> if os.name != "nt":
...     _redis_example()

Submodules#