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

My Lethal Trifecta talk at the Bay Area AI Security Meetup - 9th August 2025
The surprise deprecation of GPT-4o for ChatGPT consumers - 8th August 2025
GPT-5: Key characteristics, pricing and model card - 7th August 2025

conditions 1 effbot 4 events 108 fredrik-lundh 7 locks 1 python 1171 rlocks 1 semaphores 1 threading 7 tutorial 18

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