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fix(debug): strace the container's whole process tree by default - #9
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Attaching only to the container's init PID showed a single line (e.g. "rt_sigsuspend([], 8") and then nothing: init is usually idle, blocked waiting for signals or children, while the real activity happens in child processes that were never traced (-f only follows forks created after attaching). By default strace now enumerates the container's existing process tree from the host /proc (ProcTreePids, shared with the top fallback) and attaches to every process, plus -f for anything forked later. --pid still targets a single process, with --follow-forks opting into -f there. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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containershell straceattached only to the container's init PID, which is typically idle (blocked inrt_sigsuspend/wait4) — so the output was one interrupted-syscall line and then silence, while all real activity happened in untraced child processes (-fonly follows forks created after attach).Fix: by default, enumerate the container's existing process tree from host
/proc(reusing the walker from thetopfallback) and attach strace to every process, with-ffollowing anything forked later.--pidstill traces a single PID;--follow-forksapplies there.Verified live (rootless Podman, alpine with idle
sleepinit + active background child): attaches to all 3 processes and streams child syscalls (nanosleep,wait4,SIGCHLD, fork/exit cycles).go vet+go test -racegreen, new unit test forProcTreePids.🤖 Generated with Claude Code