fix(ext/node): handle signal 0 in child_process.kill()#32294
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bartlomieju merged 5 commits intodenoland:mainfrom Mar 11, 2026
Merged
fix(ext/node): handle signal 0 in child_process.kill()#32294bartlomieju merged 5 commits intodenoland:mainfrom
bartlomieju merged 5 commits intodenoland:mainfrom
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In POSIX, signal 0 is used to check if a process exists without actually sending a signal. Deno's `toDenoSignal` didn't recognize signal 0, causing `child.kill(0)` to throw `Unknown signal: 0`. This broke npm packages like nuxt that use `kill(0)` to check if a child process is still alive on exit. Closes denoland#25776 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Fixes resource leak on Windows where the child process wasn't fully closed before the test ended, causing cascading failures. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
kajukitli
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Mar 10, 2026
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kajukitli
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lgtm — signal 0 is a POSIX special case for checking process existence
delegates to process.kill(pid, 0) which already handles this correctly. returns true if process exists, false otherwise. doesn't set killed flag since no signal was actually sent
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Summary
child_process.kill(0)threwUnknown signal: 0becausetoDenoSignal()didn't recognize signal 0kill(pid, 0))0(both numeric and string"0") as a special case inChildProcess.kill(), usingprocess.kill(pid, 0)which already supports signal 0nuxtthat usekill(0)to check if a child process is alive on exitCloses #25776
Test plan
killSignalZeroinchild_process_test.tscargo test unit_node::child_process_testpasses🤖 Generated with Claude Code