On 28-Apr-2001 Tony Hoyle wrote:
> Is there a way (kernel or userspace... doesn't matter) that gdb/ddd
> could be invoked when a program is about
> to dump core, or perhaps on a certain signal (that the app could deliver
> to itself when required). The latter case
> is what I need right now, as I have to debug an app that breaks
> seemingly randomly & I need to halt when
> certain assertions fail. Core dumps aren't much use as you can't resume
> them, otherwise I'd just force a segfault
> or something.
>
> I had a look at the do_coredump stuff and it looks like it could be
> altered to call gdb in the same way that
> modprobe gets called by kmod... however I don't sufficiently know the
> code to work out whether it'd work properly
> or not.
Sorry but why don't You run Your application with gdb ?
Once Your program crashes You'll get the prompt and You'll be able to
stack-trace and watching whatever You need.
The solution I use to be able to get inside the program even when the gdb is
not running is the one that You can find in the attached file.
Basically it install the handler that will create a script file that You can
use to automatically enter with gdb inside Your program while it's running.
- Davide
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