help required on segmentation fault

sachintalk · 08-26-2005, 10:05 AM

Hi all,

I have multithreaded application. (pthread_create).
I did threadpooling.

I am getting Segmentation fault. (randomly)
Is there any way to know in which thread Segmentation fault has occoured.

Can i get thread_id or anything related in signal handler?

Regards,
sachin.

jim mcnamara · 08-26-2005, 11:38 AM

Did you try gdb - compiling gcc -g , etc.?

sachintalk · 08-27-2005, 02:11 AM

Hi,

i did gdb.
problem is not occouring for each run.
say it comes aftrer 10 days.

I added log per thread, but as there is multipal thread
i want to know which thread gets segmentation fault.

Regards,
sachin.

shishir · 09-05-2005, 06:49 AM

if you want to log the thread id of teh thread that was executing when the program crashed...you may want to handle the signal , sigsegv, log the pthread_self in some file or to some console and then restore the default hanler for segv and return so that the default behaviour of the signal takes up from there...

Code:

void handle(int sig)
{
      fprintf (stderr, "here with tid: %d \n", pthread_self());
      signal (SIGSEGV,SIG_DFL);
      return;
}

-shishir

paulsm4 · 09-06-2005, 01:22 AM

You can also run the program inside gdb for 10 days. Or start the program(s) and, once started, attach to it (them) with GDB.

Either way, GDB will be able to tell you a lot more. For example: how many threads were active, and their respective stackss.

sachintalk · 09-07-2005, 11:20 PM

Before running my application
i set

ulimit -c unlimited

for core dump.

I debug core file with gdb and reach to root of problem.

thanks for help.

Regards,
sachin.