fix: forward SIGINT to child process for proper Ctrl+C handling#32
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fix: forward SIGINT to child process for proper Ctrl+C handling#32
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When running shell commands, the spawned child process is in a separate process group (due to detached: true). This causes Ctrl+C to not properly terminate the child. Forward SIGINT signals to the child's process group.
The previous approach (forwarding SIGINT to child's process group via -pid) didn't work because deep descendants like vite create their own process groups. Now recursively walks the process tree and sends SIGINT to every descendant individually.
Pipe stdout/stderr (instead of inherit) so we can unpipe before killing the child tree. This suppresses pnpm's "ELIFECYCLE Command failed." message that appears when its child exits non-zero during shutdown.
…ss groups - Use stdio: 'inherit' to preserve colors, escape codes, and terminal clearing - On Ctrl+C, only SIGTERM descendants in different process groups (e.g. vite) while leaving the PM's group (pnpm/bun) untouched - This lets bun handle SIGINT naturally (prints "Shutting down", kills vite, exits 0) and pnpm sees a clean exit (no ELIFECYCLE) - Effect.uninterruptible prevents the runtime from racing to kill children
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Summary
@effect/platform'sCommandExecutor(which usesdetached: true) and spawn child processes directly via Node'schild_process.spawnWhy tree-kill instead of process group forwarding
The initial approach (
process.kill(-pid, 'SIGINT')) only reaches processes in the child's immediate process group. In practice, deep descendants like vite create their own process groups (observed: pnpm/bun in PGID X, vite in PGID Y), so they never receive the forwarded signal. Tree-kill (pgrep -Precursion) finds and signals every descendant regardless of process group.Test plan
pm devin a project with vite — Ctrl+C — no orphaned processes (lsof -i :3000clean)pm iwith Ctrl+C during install — clean exitpm run <script>with other long-running scripts