call a function even a program terminate abnormally

call a function even a program terminate abnormally

[Yubin Ruan]

Hi,
I am wondering whether it is possible to invoke a function when a program
terminate abnormally (e.g., segfault). I know "atexit(3)" will do the job
if the process terminate normally. But I am wondering whether that is possible
for the abnormal case. Any system call for this (on Linux)?

I am doing some interprocess communication here. If a process just die with
a lock unlocked, there might be potential deadlock.

Thanks,
Yubin

Re: call a function even a program terminate abnormally

[Patrick Schlangen]

Hi Yubin,

> I am wondering whether it is possible to invoke a function when a program
> terminate abnormally (e.g., segfault).

you could install a signal handler for SIGSEGV using signal() (2),
but please be aware of all the pitfalls.

When your process receives SIGSEGV, you probably have some
memory corruption ongoing and you don't know if the data structure
holding your lock is still valid.

Best Regards,

Patrick

Re: call a function even a program terminate abnormally

[Marcin Mielniczuk]

I guess you'd have to install handlers for every possible signal. Your program can receive SIGTERM, SIGKILL, ...

On August 5, 2017 11:29:51 AM GMT+02:00, Patrick Schlangen <patrick@schlangen.me> wrote:
>Hi Yubin,
>
>> I am wondering whether it is possible to invoke a function when a
>program
>> terminate abnormally (e.g., segfault).
>
>you could install a signal handler for SIGSEGV using signal() (2),
>but please be aware of all the pitfalls.
>
>When your process receives SIGSEGV, you probably have some
>memory corruption ongoing and you don't know if the data structure
>holding your lock is still valid.
>
>Best Regards,
>
>Patrick

-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Re: call a function even a program terminate abnormally

[Patrick Schlangen]

Be aware that SIGKILL cannot be caught...

Another idea would be to have a monitoring process which spawns your program, monitors it and does cleanup once it dies.

Patrick



Von meinem iPhone gesendet
> Am 05.08.2017 um 11:31 schrieb Marcin Mielniczuk <marmistrz.dev@zoho.eu>:
> 
> I guess you'd have to install handlers for every possible signal. Your program can receive SIGTERM, SIGKILL, ...
> 
>> On August 5, 2017 11:29:51 AM GMT+02:00, Patrick Schlangen <patrick@schlangen.me> wrote:
>> Hi Yubin,
>> 
>>> I am wondering whether it is possible to invoke a function when a
>> program
>>> terminate abnormally (e.g., segfault).
>> 
>> you could install a signal handler for SIGSEGV using signal() (2),
>> but please be aware of all the pitfalls.
>> 
>> When your process receives SIGSEGV, you probably have some
>> memory corruption ongoing and you don't know if the data structure
>> holding your lock is still valid.
>> 
>> Best Regards,
>> 
>> Patrick
> 
> -- 
> Sent from my Android device with K-9 Mail. Please excuse my brevity.
> 
>