Debugging X with GDB

Daniel Jacobowitz dan at
Mon Jan 11 06:01:56 PST 2010

On Sun, Jan 10, 2010 at 07:42:16PM -0500, Bernie Innocenti wrote:
> <airlied> I think X might change TTY state and piss gdb off

I'd imagine this is it, but it's impossible to tell without debugging
the TTY state.

When you hit ^C, that doesn't necessarily cause anything to happen.
The TTY subsystem sees ^C, and may or may not generate a SIGINT to the
foreground process group depending on the tty settings; try checking
using stty -F, for instance.  Then the foreground process group is X,
not GDB; if the SIGINT is blocked or ignored, it won't be delivered,
so GDB can't intercept it at delivery.

Using ^C is not always reliable.

Daniel Jacobowitz

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