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

The Summer of Johann: prompt injections as far as the eye can see - 15th August 2025
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LLM 0.27, the annotated release notes: GPT-5 and improved tool calling - 11th August 2025

conditions 1 effbot 4 events 108 fredrik-lundh 7 locks 1 python 1179 rlocks 1 semaphores 1 threading 7 tutorial 18

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