Re: [RFA] Fix troubles with watchpoints in DJGPP

[Eli Zaretskii <eliz at gnu dot org>]

> 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.