LinuxProcess: Start stdin relay after process start#478
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dcantah merged 1 commit intoapple:mainfrom Jan 16, 2026
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Because we start piping stdin before process launch we can fill up the guest pipe buffer before the process even starts. We'd need some backpressure mechanism to handle this (register the other end with epoll and buffer some data etc.), but we should probably just start piping after the process is up and running. This change does exactly that, as well as stops holding the process mutex while draining stdin in the guest for `CloseStdin()`. This fixes issues where we try and write > pipe_buf bytes through stdin. Today this hangs.
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Fixes #477
Because we start piping stdin before process launch we can fill up the guest pipe buffer before the process even starts. We'd need some backpressure mechanism to handle this and slow consumers (register the other end with epoll and buffer some data etc.), but we should probably just start piping after the process is up and running. This change does exactly that, as well as stops holding the process mutex while draining stdin in the guest for
CloseStdin().This fixes issues where we try and write > pipe_buf bytes through stdin. Today this hangs.