daemon under runit?

daemon under runit?

[Toni Mueller]

Hello,

I'm struggling with a program that, in many cases, forks to become a
daemon, that I'd like to run under runit (1.7.1). So far, I tried to
start the program in the run script, then wait in a 'finish' script for
it, and also have a control/t script to kill it if someone says
something like "sv down service". Unfortunately, in most cases, this
does not seem to work - the control/t script is not accessed when I
issue 'sv down service' (as "ls -lta" shows). One of the problems is
that the file supervise/pid contains the pid of the finish script in
case the program forked, no longer the pid of the daemon itself. I
hoped to achieve something similar to fghack (from daemontools), but so
far failed.

This is on Debian GNU/Linux, kernel 2.6.18.


Any ideas are _very_ welcome!


Best,
--Toni++

Re: daemon under runit?

[Alex Efros]

Hi!

On Tue, Dec 05, 2006 at 11:34:42PM +0100, Toni Mueller wrote:
> I'm struggling with a program that, in many cases, forks to become a

"in many cases"?! I.e. it fork sometimes and sometimes don't fork?! ;-)

> daemon, that I'd like to run under runit (1.7.1). So far, I tried to
> start the program in the run script, then wait in a 'finish' script for
> it, and also have a control/t script to kill it if someone says
> something like "sv down service". Unfortunately, in most cases, this
> does not seem to work - the control/t script is not accessed when I
> issue 'sv down service' (as "ls -lta" shows). One of the problems is

You should use control/d instead of control/t if you wish to catch `sv down`.

> that the file supervise/pid contains the pid of the finish script in
> case the program forked, no longer the pid of the daemon itself. I
> hoped to achieve something similar to fghack (from daemontools), but so
> far failed.
 
It's usually simple enough to patch any program to not fork.

-- 
			WBR, Alex.

Re: daemon under runit?

[Toni Mueller]

Alex Efros wrote:
> On Tue, Dec 05, 2006 at 11:34:42PM +0100, Toni Mueller wrote:
>> something like "sv down service". Unfortunately, in most cases, this
>> does not seem to work - the control/t script is not accessed when I
>> issue 'sv down service' (as "ls -lta" shows). One of the problems is
> 
> You should use control/d instead of control/t if you wish to catch `sv down`.

Well, the man page says that control/t is executed before d or x on
either 'down' or 'exit'. From http://smarden.sunsite.dk/runit/runsv.8.html:

"On command d first service/control/t is checked, and then
service/control/d. On command x first service/control/t is checked, and
then service/control/x."

> It's usually simple enough to patch any program to not fork.

That's what I eventually did.

Thank you!


Best,
--Toni++