Starting service daemons

[Denis Vlasenko]

On Tuesday 27 March 2007 13:28, hinko.kocevar at cetrtapot.si wrote:
> Natanael Copa wrote:
> > On Tue, 2007-03-27 at 09:16 +0200, hinko.kocevar at cetrtapot.si wrote:
> >> Hello,
> >>
> > 
> > Use start-stop-daemon -n or with pidfiles.
> > 
> 
> Ok, thanx.
> I've tried -m -p /var/lock/pidfile and strange thing happens - actual 
> PID number recoreded in the pidfile doesn't belong to the daemon being 
> started. It belongs to the process that already finished. Eg.
> 
> # start-stop-daemon --start -m -p /var/lock/crond.pid -x /sbin/crond -- 
> -c /etc/crontab/
> 
> # ps
> ...
>   4274 root        192 S   /sbin/crond -c /etc/crontab/
> 
> # cat /var/lock/crond.pid
> 4272

start-stop-daemon --start -m -p z.pid -x /bin/sleep 100

Pidfile contains 12422

and in ps output I see:

12422 root     /bin/sleep 100

You don't see it because you start _self-daemonizing_ applets -
they fork and then parent exits. Of course start-stop-daemon
records PID of parent process!

Which leads me to a question "why do you need start-stop-daemon
at all" if you can do the same in shell:

#!/bin/sh
echo $$ >z.pid; exec /bin/sleep 100

Simple, huh?
--
vda