Re: [Expectperl-discuss] Strange time out and hard close

[<ex...@ih...>]

On Tue, 23 Jul 2002 11:05:21 +0200
Roland Giersig <RGi...@cp...> wrote:

> > Ok, I know it's not healthy to talk to myself.... ;^)
> 
> Well, it's a start... :-)
> 
> > The problem seems to be some difference in how regex is handled.
> > 
> > If I just do $obj->expect(undef, $item);
> > everything works fine.
> > 
> > If I use instead $obj->expect(undef, -re => "$item");
> > Things fail mysteriously (to me anyway).  I'm certain that my
> > understanding
> > of this module is incomplete so it's possible that I'm missing the
> > distinction between these 2 idioms.
> 
> perldoc Expect:
> 
>   Changed from older versions is the regular expression
>   handling. By default now all strings passed to expect()
>   are treated as literals. To match a regular expression
>   pass '-re' as a parameter in front of the pattern you
>   want to match as a regexp.
> 
>   Example:
> 
>    $object->expect(15, 'match me exactly','-re','match\s+me\s+exactly');
> 
> Anything unclear with that?  Should the docs be worded differently?
> 
> > > > The spawned program is an sh script.  The timeout comes only after
> > > > a few seconds at one point when the script is doing work.
> > > > Why is it timing out?  Is something strange happening to
> > > > $end_time?
> > > > 
> > > > Here's the bit of code from Expect.pm that gets me
> > > > to this point:
> > > > 
> > > > 1329:    if (($end_time <= time()) && ${*$self}{exp_Debug}) {
> > > > 1330:      print STDERR "Timed out waiting for an EOF from
> > ${*$self}{exp_Pty_Handle}.\r\n";
> > > > 1331:    }
> > > > 
> > > > Can anyone provide any clues? 
> 
> Without you providing more code?  No.

Don't think we're on the same wavelength, I suspect that it's my fault for
not providing enough info. I do understand "-re", I do not understand why
"-re" fails and when I don't specify "-re" things are fine.

In my previous post I noted that I was seeing this which
I only saw when I used $obj->expect(undef, -re => "$item");
and this showed up
Use of uninitialized value in concatenation (.) or string at /usr/btools/perl/lib/site_perl/5.6.1/Expect.pm line 1388


If I use this I have no problems:
$obj->expect(undef, $item);


So what's different about the code path for those two that causes one to fail?

Essentially that's all the code there is, it waits for a string which is a "key"
value and provides the corresponding "value" value. It almost appears as if the 
-re idiom is not respecting the undef for the timeout value and therefore is
not waiting indefinitely.