Re: Expect fails to recognize regexp

Daniel Jacobowitz
2002-09-13T18:15:43Z

On Fri, Sep 13, 2002 at 08:06:43PM +0200, Corinna Vinschen wrote:
> Hi,
>
> I'm trying to fix an error in the testsuite lib but I'm stuck at one
> point. For some mysterious reason, I can't get a regexp right.
>
> Ok, the original preoblem I'm trying to solve is, that in lib/gdb.exp,
> proc rerun_to_main() the procedure doesn't take into account, that
> some targets never actually exit, but instead are programatically
> trapped in some _exit function.
>
> This means that rerun_to_main() must be able to manage the situation
> that gdb not just reruns, but first asks
>
> The program being debugged has been started already.
> Start it from the beginning? (y or n)
>
> What I did was adding the following patch to gdb.exp:
>
> Index: lib/gdb.exp
> ===================================================================
> RCS file: /cvs/src/src/gdb/testsuite/lib/gdb.exp,v
> retrieving revision 1.26
> diff -u -p -r1.26 gdb.exp
> --- lib/gdb.exp 13 Sep 2002 17:20:11 -0000 1.26
> +++ lib/gdb.exp 13 Sep 2002 17:59:35 -0000
> @@ -1685,6 +1685,10 @@ proc rerun_to_main {} {
> } else {
> send_gdb "run\n"
> gdb_expect {
> + -re "The program .* has been started already.*y or n. $" {
> + send_gdb "y\n"
> + exp_continue
> + }
> -re "Starting program.*$gdb_prompt $"\
> {pass "rerun to main" ; return 0}
> -re "$gdb_prompt $"\
>
> but it doesn't work! I tried various... uhm... variations of the
> expression, include simple stuff as
>
> -re "The program.*"
>
> or moving the -re back and forth in the gdb_expect expression but to
> no avail. The result in gdb.log was always the same:
>
> (gdb) PASS: gdb.base/ena-dis-br.exp: continue until exit at no stop
> run^M
> The program being debugged has been started already.^M
> Start it from the beginning? (y or n) FAIL: gdb.base/ena-dis-br.exp:
> (timeout) rerun to main
>
> As you can see, there's no 'y' in the log so expect didn't recognize
> the expression at all.
>
> Does anybody have an idea what's going on here?

What do you get if you put "exp_internal 1" before this expression?

[This is why I loathe DejaGNU sometimes. TCL/Expect are very...
picky.]

--
Daniel Jacobowitz
MontaVista Software Debian GNU/Linux Developer