[syslog-ng] program destination and init??

[Thomas Wollner]

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Hi,

this issue is fixed in current 3.3.3 too.
Scripts spawned by program destination are receiving the TERM signal
upon restart.

Thank you,

Best regards,

Tom


On 18.12.2011 10:05, Balazs Scheidler wrote:
> On Fri, 2011-12-02 at 14:57 +0100, Gergely Nagy wrote:
>> Thomas Wollner <tw at wollner-net.de> writes:
>> 
>>> Hi,
>>> 
>>> I had a similar situation on debian squeeze a while ago. in
>>> debian 6 the default system shell is dash and syslog-ng hands
>>> over program destinations to the standard system shell. I
>>> changed the /bin/sh link from /bin/dash to /bin/bash and
>>> everything works as expected.
>> 
>> I believe I know why this happens, but I still need to test my 
>> suspicion: bash has an optimisation, that when a program is
>> executed as "/bin/bash -c command", bash will exec it (as in, it
>> will do the same as if one called "exec command" from the
>> shell).
>> 
>> Dash doesn't do this, and this might lead to the different
>> behaviour.
>> 
>> This will still need to be solved on the syslog-ng side, but I do
>> not yet know how. I'll post a patch or more information as I
>> progress further.
>> 
> 
> Perhaps adding "exec" in front of the command line? syslog-ng needs
> a pid to the child in order to kill it.
> 
> dash seems to fork an extra time, and doesn't propagate signals it 
> receives to its children.
> 
> syslog-ng is documented to spawn programs using the shell, however
> then it also needs signals.
> 
> Another alternative is to send signals to the whole group, but
> that might cause problems if the executed program itself wants to
> handle SIGTERM gracefully by doing something with its children (w/o
> SIGTERM)
> 
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