Re: How to debug a hang process if the hung process itself is gdb !

[Michael Snyder <msnyder@vmware.com>]

Attach is the only way I know of.

Santosh Pradhan wrote:
> Hi Mike,
> Thanks for the quick response. I tried to attach the hung gdb to fresh gdb and it says _PTRACE operation not permitted. :( IS there any way to debug the hung gdb?
> 
> Thanks,
> Santosh
> 
> On Tue, Oct 5, 2010 at 11:10 PM, Michael Snyder <msnyder@vmware.com<mailto:msnyder@vmware.com>> wrote:
> santoshp wrote:
> Hi All,
> I have a problem, I have a signal handler for few fatal signals e.g.
> sigsegv, sigill etc. The handler will dump the stack trace in the log when
> those signals will be triggered using GDB in batch mode. What I do is fork()
> a process and inside the child I exec() the gdb process to capture the stack
> tarce. The command will be something like this:
> 
> /usr/bin/gdb <binary path> <running pid> -batch -n -x <command file>
> 
> cat $commandfile
> 
> set pagination off
> set width 65536
> thread apply all bt
> detach
> 
> But it seems the gdb itself hung and the process attached is also hung. How
> to debug them ?
> 
> Is there a way to see the stack trace for hung gdb process or the running
> process to be debugged which was attached to gdb?
> 
> If anybody knows of any known issues with GDB, please share.
> 
> GDb version: GNU gdb Red Hat Linux (6.5-37.el5_2.2rh),
> "x86_64-redhat-linux-gnu", OS is RHEL5 running on x86_64. Please let me know
> if this is not the place to discuss this. Any help or pointer would be of
> great help.
> 
> 
> Thanks in advance.
> 
> Regards,
> Santosh
> 
> 
> Have you tried attaching a fresh gdb to the hung gdb?
> 
> 
> 
>