bionic (1) timelimit.1.gz

NAME

     timelimit — effectively limit the absolute execution time of a process

SYNOPSIS

     timelimit [-pq] [-S killsig] [-s warnsig] [-T killtime] [-t warntime] command [arguments ...]

DESCRIPTION

     The timelimit utility executes a given command with the supplied arguments and terminates the spawned
     process after a given time with a given signal.  If the process exits before the time limit has elapsed,
     timelimit will silently exit, too.

     Options:

     -p      If the child process is terminated by a signal, timelimit propagates this condition, i.e. sends the
             same signal to itself.  This allows the program executing timelimit to determine whether the child
             process was terminated by a signal or actually exited with an exit code larger than 128.

     -q      Quiet operation - timelimit does not output diagnostic messages about signals sent to the child
             process.

     -S killsig
             Specify the number of the signal to be sent to the process killtime seconds after warntime has
             expired.  Defaults to 9 (SIGKILL).

     -s warnsig
             Specify the number of the signal to be sent to the process warntime seconds after it has been
             started.  Defaults to 15 (SIGTERM).

     -T killtime
             Specify the maximum execution time of the process before sending killsig after warnsig has been
             sent.  Defaults to 120 seconds.

     -t warntime
             Specify the maximum execution time of the process in seconds before sending warnsig.  Defaults to
             3600 seconds.

     On systems that support the setitimer(2) system call, the warntime and killtime values may be specified in
     fractional seconds with microsecond precision.

ENVIRONMENT

     KILLSIG
             The killsig to use if the -S option was not specified.

     KILLTIME
             The killtime to use if the -T option was not specified.

     WARNSIG
             The warnsig to use if the -s option was not specified.

     WARNTIME
             The warntime to use if the -t option was not specified.

EXIT STATUS

     If the child process exits normally, the timelimit utility will pass its exit code on up.  If the child
     process is terminated by a signal and the -p flag was not specified, the timelimit utility's exit status is
     128 plus the signal number, similar to sh(1).  If the -p flag was specified, the timelimit utility will
     raise the signal itself so that its own parent process may in turn reliably distinguish between a signal
     and a larger than 128 exit code.

     In rare cases, the timelimit utility may encounter a system or user error; then, its exit status is one of
     the standard sysexits(3) values:

     EX_USAGE
             The command-line parameters and options were incorrectly specified.

     EX_SOFTWARE
             The timelimit utility itself received an unexpected signal while waiting for the child process to
             terminate.

     EX_OSERR
             The timelimit utility was unable to execute the child process, wait for it to terminate, or examine
             its exit status.

EXAMPLES

     The following examples are shown as given to the shell:

           timelimit -p /usr/local/bin/rsync rsync://some.host/dir /opt/mirror

     Run the rsync program to mirror a WWW or FTP site and kill it if it runs longer than 1 hour (that is 3600
     seconds) with SIGTERM.  If the rsync process does not exit after receiving the SIGTERM, timelimit issues a
     SIGKILL 120 seconds after the SIGTERM.  If the rsync process is terminated by a signal, timelimit will
     itself raise this signal.

           tcpserver 0 8888 timelimit -t600 -T300 /opt/services/chat/stats

     Start a tcpserver(n) process listening on tcp port 8888; each client connection shall invoke an instance of
     an IRC statistics tool under /opt/services/chat and kill it after 600 seconds have elapsed.  If the stats
     process is still running after the SIGTERM, it will be killed by a SIGKILL sent 300 seconds later.

           env WARNTIME=4.99 WARNSIG=1 KILLTIME=1.000001 timelimit sh stats.sh

     Start a shell script and kill it with a SIGHUP in a little under 5 seconds.  If the shell gets stuck and
     does not respond to the SIGHUP, kill it with the default SIGKILL just a bit over a second afterwards.

SEE ALSO

     kill(1), rsync(1), signal(3), tcpserver(n)

STANDARDS

     No standards documentation was harmed in the process of creating timelimit.

BUGS

     Please report any bugs in timelimit to the author.

AUTHOR

     The timelimit utility was conceived and written by Peter Pentchev <roam@ringlet.net> with contributions and
     suggestions by Karsten W Rohrbach <karsten@rohrbach.de>, Teddy Hogeborn <teddy@fukt.bsnet.se>, and Tomasz
     Nowak <nowak2000@poczta.onet.pl>.