Re: [RFA] Fix troubles with watchpoints in DJGPP

Eli Zaretskii
2009-05-28T13:27:26Z

> From: "Pierre Muller" <muller@ics.u-strasbg.fr>
> Cc: <gdb-patches@sourceware.org>
> Date: Thu, 28 May 2009 11:31:22 +0200
>
> > > > > (bad file descriptor errors when trying to restart
> > > > > a ./gdb executable at level 2, meaning inside another gdb
> > > > > itself being debugged by gdb).
> >
> > Can you show an example of these ``bad file descriptor errors''? I
> > don't think I ever saw them.
>
> This one is more tricky, I only saw it with 3 levels of gdb.
> And maybe watchpoints were needed too...
> I will try to find a reproducible way, but it might not be so easy.

Thank you.

> What I am missing is a FSEXT hook call inside dup
> so that I know that the return value of dup is used,
> instead with current gdbcom.c code, I will only get a
> call to dbg_fsext when this handle is closed, but
> at that point, I would have no idea where this handle is coming from!

But you can set a breakpoint on dup itself, can't you? Then you will
see both the input descriptor and the one it returns to the caller.