Re: Signal handling

Yes,

This is something that should exist. I will add it to the TODO list.

Not just for SIGTERM related events, but also as safety precautions for 
killed applications. When a SIGKILL is sent, Dazuko in many situations 
does not receive *any* indication of this. It goes on assigning access 
control to the non-existant process, causing the machine to have a 
hanging effect. :(

Dazuko has severe problems when dealing with "unfriendly" situations 
(SIGSTOP, SIGKILL, exitting without unregistering). This must be improved.

John Ogness


S Wade wrote:
> Is it realistic to search the process table for the application after 
> receiving a SIGTERM to determine whether or not to unregister the 
> application?
> 
> Swade
> 
> 
>> From: John Ogness <[email protected]>
>> To: Jaroslav Suchanek <[email protected]>
>> CC: Dazuko devel <[email protected]>
>> Subject: Re: [Dazuko-devel] Signal handling
>> Date: Thu, 28 Aug 2003 12:22:47 +0200
>>
>> Hi,
>>
>> Which version of Dazuko are you using? This is a bit of a controversial
>> issue, and I am not sure how to handle it.
>>
>> In the new pre-release version of Dazuko, a SIGTERM to the registered
>> application will not only cause dazukoGetAccess to return with an error,
>> but it will also unregister the applicatoin with Dazuko!
>>
>> This would be dangerous for applications that will continue working,
>> even though a SIGTERM has been sent. The advantage of this, is it allows
>> Dazuko to avoid problems of applications not unregistering themselves
>> before they quit. However, I am not happy about this and will be
>> changing it before the next version is released.
>>
>> So what should Dazuko do?
>>
>> Do you think dazukoGetAccess should continue blocking, even though a
>> SIGTERM has been sent? In my opinion this is not an option, since the
>> application *must* have a chance to exit if it wants.
>>
>> A good solution would be if different error codes were returned (rather
>> than simply !0). Then you could know if dazukoGetAccess failed because
>> of some real problem, or because an interruption signal was sent. What
>> do you think?
>>
>> John Ogness
>>
>>
>> Jaroslav Suchanek wrote:
>> > Hi,
>> >
>> > Is it correct, that after sending signal (e.g. SIGTERM) function
>> > dazukoGetAccess always return error code?
>> >
>> > Is there any way, how to handle signal and continue working with 
>> dazuko?
>> >
>> > Thanks for all ideas,
>> >
>> > Jaroslav Suchanek