Fix native mode crash on Linux Python 3.14 (forkserver default) - #156
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evnchn wants to merge 1 commit into
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Fix native mode crash on Linux Python 3.14 (forkserver default)#156evnchn wants to merge 1 commit into
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Fixes zauberzeug#6062. zauberzeug#6045 migrated the native-mode IPC primitives (Queue, Pipe, Event) to SPAWN_CONTEXT but left the Process on the default context. Python 3.14 changed the Linux default start method from 'fork' to 'forkserver', which re-imports the user's main module to bootstrap workers but does NOT use the '--multiprocessing-fork' argv trampoline that lets mp.freeze_support() short-circuit, so the doc example crashes with: RuntimeError: An attempt has been made to start a new process before the current process has finished its bootstrapping phase. Switching the Process to SPAWN_CONTEXT keeps every native-mode IPC primitive on the same context and works on all supported Pythons: spawn's trampoline runs the target and exits the child before reaching ui.run() on re-import, so app.native.window_args / start_args / settings set in the user script still propagate correctly.
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Spike for upstream issue zauberzeug/nicegui#6062. Completes the spawn-context migration started in #6045, which moved Queue/Pipe/Event to
SPAWN_CONTEXTbut leftmp.Processon the default context.Python 3.14 changed the Linux multiprocessing default from
forktoforkserver. Forkserver re-imports the user's main module to bootstrap workers but does not use the--multiprocessing-forkargv trampoline, somp.freeze_support()cannot short-circuit and_check_not_importing_main()raises:Fix: one-line change to
native.SPAWN_CONTEXT.Process(...). Spawn's trampoline runs the target and exits before reachingui.run()in the child, soapp.native.window_args/start_args/settingsset in the user script still propagate correctly (verified empirically on Linux 3.14.5 and macOS 3.14.4).