Run a command with a time limit, runs the given command and kills it if it is still running after the specified time interval.
Syntax
timeout [option] duration command [arg]...
Key
command
The command to execute, this must not be a special built-in utility.
Options must precede operands.
--preserve-status
Return the exit status of the managed command on timeout, rather than
a specific exit status indicating a timeout.
This is useful if the managed command supports running for an
indeterminite amount of time.
--foreground
Don't create a separate background program group, so that the
managed command can use the foreground TTY normally.
This is needed to support timing out commands not started directly
from an interactive shell, in two situations.
1) command is interactive and needs to read from the terminal for example.
2) The user wants to support sending signals directly
to command from the terminal (like Ctrl-C for example)
Note in this mode of operation, any children of command will not be timed out.
-k duration
--kill-after=duration
Ensure the monitored command is killed by also sending a ‘KILL’ signal, after
the specified duration.
Without this option, if the selected signal proves not to be fatal, timeout
does not kill the command.
-s signal
--signal=signal
Send this signal to command on timeout, rather than the default ‘TERM’ signal.
signal can be a name like ‘HUP’ or a number. See Signal specifications.
duration is a floating point number followed by an optional unit:
‘s’ for seconds (the default)
‘m’ for minutes
‘h’ for hours
‘d’ for days
A duration of 0 disables the associated timeout.
Note that the actual timeout duration is dependent on system conditions,
which should be especially considered when specifying sub-second timeouts.
--help
Print a usage message listing all available options, then exit successfully.
--version
Print the version number, then exit successfully.
-- Delimit the option list. Later arguments, if any, are treated as operands
even if they begin with -. For example, ‘sort -- -r’ reads from the file
named -r.
Exit status:
124 if command times out
125 if timeout itself fails
126 if command is found but cannot be invoked
127 if command cannot be found
137 if command is sent the KILL(9) signal (128+9)
The exit status of command otherwise
The timeout command debuted in Coretuils 7.0 Beta (2008-10-05)
Examples
Run a command (LongRunningCommand) and timeout after 1 minute if the process has not completed already:
$ timeout 1m LongRunningCommand
Running date before and after the command will show how long it took:
$ date; timeout 1m LongRunningCommand; date
Apply a 10 second time out to a crontab task
$ 0 1 * * * cronuser timeout 10s demo-script
“There will be a time when loud-mouthed, incompetent people seem to be getting the best of you. When that happens, you only have to be patient and wait for them to self destruct. It never fails” ~ Richard Rybolt
Related linux commands:
crontab - Schedule a command to run at a later time.
time - Measure Program running time.
timelimit - Limit a process’s absolute execution time (Debian).