Restarting a daemon

[Albert Hopkins]

On Tue, 2011-04-26 at 06:13 -0600, Jeffrey Barish wrote:
> Not exactly a Python question, but I thought I would start here.
> 
> I have a server that runs as a daemon.  I can restart the server manually 
> with the command 
> 
> myserver restart
> 
> This command starts a new myserver which first looks up the pid for the one 
> that is running and sends it a terminate signal.  The new one then 
> daemonizes itself.
> 
> I want the server to be able to restart itself.  Will it work to have 
> myserver issue "myserver restart" using os.system?  I fear that the new 
> myserver, which will be running in a subshell, will terminate the subshell 
> along with the old myserver when it sends the terminate signal to the old 
> myserver.  If so, what is the correct way to restart the daemon?  Will it 
> work to run the restart command in a subprocess rather than a subshell or 
> will a subprocess also terminate when its parent terminates?

You should look into tools like daemon-tools, or similar.  It already
solves this (and many other) problems.

-a