Automatic backtrace [Was: Re: NetAPP/Samba 3.0/plugs]

[Scott Gifford]

Tim Potter <tpot at samba.org> writes:

> On Thu, Mar 14, 2002 at 08:47:39AM +1100, Andrew Bartlett wrote:
> 
> > > "Esh, Andrew" wrote:
> > > 
> > > Can the smbd process pid be passed to a panic action?
> > 
> > Yes, %d.  I have a panic action that opens an xterm with gdb already in
> > it.
> > 
> > What I think would be nice is if we could make the stdout/stderr of
> > 'panic action' end up in the current logfile.  That should not be that
> > hard actually...

Probably this should be optional, to make sure that your gdb xterm
trick still works.  Maybe output could be sent to the logfile if the
last character of the panic action command was "|", as in Perl:

    panic action = /path/to/backtrace_script|

> > Then, by using echo "bt full" | gdb /proc/%d/exe %d  we have the
> > backtrace in the logfile.  The tricky bit is getting the path to the exe
> > and the gdb stuff portably, not the actual script.

[...]

> If you're not running on Linux then you might be able to use argv[0]
> as the path to the executable or some other combination of tricks.

Especially if, when Samba starts up, it saves the current working
directory and the $PATH.

Other OS's come with other debuggers, too, such as dbx and adb.  It
may be worth considering supporting those.  Maybe a backtrace shell
script could search for one of several supported debuggers, and then
know how to get a backtrace from it.

-----ScottG.