Re: Check if gdbsx is running

[Ian Campbell <ian.campbell@citrix.com>]

On Sat, 2015-12-26 at 23:38 +0000, Andrew Cooper wrote:
> On 26/12/2015 23:27, Carl Patenaude Poulin wrote:
> > Hi all,
> > 
> > I'm writing some development tools for my team. Given a domain ID,
> > is there a way to programmatically check whether gdbsx is running on
> > that domain and what port it's running on? I could use something
> > like `top -b -n 1 | grep gdbsx` but that seems very brittle.
> With a XEN_DOMCTL_getdomaininfo hypercall, "flags & XEN_DOMINF_debugged"
> (or xc_dominfo_t.debugged) will tell you whether a debugger is attached
> to a domain.
> 
> This is the closest I am aware of you being able to get.
> 
> Whether gdbsx is running, or what port it is running on, are internal
> details to the domain running the debugger and not interesting to Xen.
> 
> If you can assume that all debuggers are run in dom0, then some process
> list based approach is probably best.

Or patching gdbsx to leave a dropping (akin to a pid file) pointing to the
correct port for a named domain (e.g. /var/run/gdbsx.$domid.port or
something in xenstore maybe?).

Or even make it able to use a named pipe or Unix domain socket instead of a
port (assuming the gdb client supports the same).

Ian.