Re: debugging a program which spawns multiple children

On 2018-02-12 08:19 PM, Christian Groessler wrote:
> Hi,
> 
> I'm trying to debug a problem in FreeBSD's "dump" command. The dump 
> command creates 4 or 5 child processes,
> and in my use case one of them gets a SIGSEGV.
> 
> Is it possible to monitor all spawned processes simultaneously? I'm 
> currently using gdb version 7.12.1 from the FreeBSD ports.
> I would have to problem to use a newer version of gdb and compile it 
> locally.
> 
> regards,
> chris
> 

Hi Christian,

If GDB for FreeBSD supports it, you can keep debugging the parent process as
well as child processes by using "set detach-on-fork off".  John (in CC) may
give more info about the support for multi process debugging with FreeBSD.

You might want to read more about the "all-stop" vs "non-stop" modes in the GDB
documentation and their related settings.

Simon