Simon Willison’s Weblog

Thread Synchronization Mechanisms in Python. Locks, RLocks, Semaphores, Events and Conditions as explained by Fredrik Lundh.

Posted 29th July 2007 at 9:32 pm

Recent articles

Distributing Go binaries like sqlite-scanner through PyPI using go-to-wheel - 4th February 2026
Moltbook is the most interesting place on the internet right now - 30th January 2026
Adding dynamic features to an aggressively cached website - 28th January 2026

conditions 1 effbot 4 events 108 fredrik-lundh 7 locks 1 python 1225 rlocks 1 semaphores 1 threads 18 tutorial 18

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