timeout

Run a command with a time limit (30 seconds)

$ timeout 30s [command]

$ timeout 5m [command]

$ timeout --signal=SIGKILL 10s [command]

$ timeout --kill-after=10s 30s [command]

$ timeout --preserve-status 5s [command]

$ timeout --foreground 30s [command]

timeout [options] duration command [args...]

timeout runs a command with a specified time limit. If the command doesn't complete within the duration, timeout sends a signal (SIGTERM by default) to terminate it.
The default signal (SIGTERM) allows processes to clean up before exiting. For processes that ignore SIGTERM, use --kill-after to send SIGKILL after an additional grace period.
Exit status is 124 if the command times out, 137 if killed by SIGKILL, or the command's own exit status if it completes within the limit. Use --preserve-status to return the signal number + 128 on timeout.

-k duration, --kill-after=duration

Send SIGKILL after additional duration if command still running

Signal to send on timeout (default: SIGTERM)

Return command's exit status even on timeout

Don't create new process group (for terminal interaction)

Diagnose signal sent to stderr

s: Seconds (default)
m: Minutes
h: Hours
d: Days
Numbers can be floating-point: 1.5m = 90 seconds

Timeout creates a new process group by default, which can interfere with interactive commands or terminal I/O. Use --foreground for such cases.
Commands that spawn child processes may leave orphaned children. Timeout only signals the direct child, not grandchildren.
Very short timeouts (sub-second) may not be reliable due to scheduling overhead.

time(1), watch(1), kill(1), sleep(1)