Monitor is a project mainly written in C, it's free.
This is a simple process monitor for situations in which you would like to restart something when it fails but aren't looking for the complexity of solution such as DaemonTools, Runit, Upstart_, and similar.
You run it like this::
monitor command [options]
This will go to the background, where monitor will fork off command and
wait for it to exit. If the command exits successfully, monitor will
exit as well. If the command exits with an error, monitor will restart
it.
Monitor uses an exponential backoff mechanism to prevent a failure from turning into a DOS attack.
-p pidfile
Write monitor's process id to pidfile. Relative paths will be relative to workdir.
The pidfile is removed when monitor exits.
-d workdir
Change to workdir before starting your command.
-f
Run in the foreground.
-I interval
If the child process exits before running at least interval seconds, activate the exponential backoff mechanism. This will cause monitor to sleep for 1 seconds before restarting the command, then 2 seconds, and so forth up to interval seconds.
The default interval is 60.
Monitor logs to the syslog DAEMON facility. When running the for
foreground, monitor will also log to stderr.
SIGINT and SIGHUP are ignored by montor but will be passed on to
the child process.
SIGTERM and SIGQUIT will be passed on to the child process.
Monitor will wait for the child process to exit and will send a SIGKILL
if the process does not exit after a few seconds. Monitor will then exit.
Copyright (c) 2011, Lars Kellogg-Stedman All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software includes a soure file from daemonize_, by Brian M. Clapper, which requires the following notice:
Copyright 2003-2011 Brian M. Clapper. All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
Neither the name "clapper.org" nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.. _daemontools: http://cr.yp.to/daemontools.html .. _runit: http://smarden.org/runit/ .. _upstart: http://upstart.ubuntu.com/ .. _daemonize: http://software.clapper.org/daemonize/