timeout on Linux (GNU coreutils) kills or signals a command after N seconds — searched for backup scripts that hang on NFS, runaway curl, or cron jobs that overlap.
Related: service watchdog,
cron,
kill & pkill.
Basic limit
Sends SIGTERM after duration, then SIGKILL if process ignores it.
bashbasic
timeout 10 sleep 60; echo exit=$?
Exit code 124
Scripts can branch on timeout vs real failure.
bashcheck
if timeout 3 ping -c 100 8.8.8.8; then echo ok; else echo code=$?Grace period
-k waits extra seconds after SIGTERM before SIGKILL.
bashkill
timeout -k 5 30 some-long-job.shPreserve partial output
Pair with tee or log files before timeout ends the process.
Warningtimeout does not limit CPU of child daemons that re-exec — use cgroup/ systemd for long-running services.
Quick Reference
- Run:
timeout 30s command - Timed out exit: 124
- Grace:
timeout -k 10 30 cmd
Related tutorials
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