Process termination monitoring implementation on Linux conflicts with processes spawned by other means #83
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Process termination monitoring is started asynchronously with the closure which receives the Execution, meaning any use of Execution in the body to send signals, etc., may send them to a pid which no longer refers to the original process. The cleanup handler may also run after the process has already terminated. This compounds with the fix for #82 (#83) to fully resolve the race conditions.
iCharlesHu
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… processes spawned by other means The approach used by Subprocess to monitor subprocess termination on Linux is fundamentally flawed as it calls waitid with P_ALL, and WEXITED without WNOWAIT, which will end up reaping pids that were spawned outside the Subprocess library. Use an implementation more like swift-testing does for wait tests, which doesn't suffer from this issue. Closes #82
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Process termination monitoring is started asynchronously with the closure which receives the Execution, meaning any use of Execution in the body to send signals, etc., may send them to a pid which no longer refers to the original process. The cleanup handler may also run after the process has already terminated. This compounds with the fix for #82 (#83) to fully resolve the race conditions.
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The approach used by Subprocess to monitor subprocess termination on Linux is fundamentally flawed as it calls waitid with P_ALL, and WEXITED without WNOWAIT, which will end up reaping pids that were spawned outside the Subprocess library.
Use an implementation more like swift-testing does for wait tests, which doesn't suffer from this issue.
Closes #82