Re: [Expectperl-discuss] pipeline question (fwd)

[<gl...@ma...>]

Forwarded message:
> From: "Roland Giersig" <Ro...@a1...>
> To: gl...@ma...
> Cc: exp...@li...
> Date: Mon, 23 Jul 2001 17:07:52 +0200
> 
> > I am trying to do something like this:
> > 
> > $ob=Expect->spawn("rsh machine command arg | localcmd");
> > 
> > I get the impression that spawn cannot handle the pipeline.
> 
> Right, this is a bug, I will fix it in v1.12, which I'm testing
> and preparing for release right now.  But due to my pending vacation
> it will only be released mid to end of august.
> 
> You can of course just patch your copy of Expect.pm, simply
> substitute the "exec(@_)" inside sub spawn with "exec($cmd)".

Thanks :)  I'm about to try it out...

> > I am guessing that I need to do this:
> > 
> > $ob1=Expect->spawn("rsh machine command arg");
> > $ob2=Expect->spawn("localcmd");
> > 
> > and then use interconnect ....???
> 
> This is one possiblity, but probably not the best.  What is that
> localcmd you want to run at the end of the pipeline?  
> Couldn't you just use qx(rsh machine | localcmd) instead of expect and
> then process the output by regular means?  I can't imagine
> a case where a program within a pipe requires user interaction.
> 
> Oh, maybe rsh is asking for a password? ...

Nope.
Since you're interested, this is the guts of what I am trying to do:

spawn("rsh machine dump_cmd various args... mount-point |cat -|dd bs=64k of=tape-device");

then use expect to catch the message:
"End of tape reached.  Press RETURN when new tape loaded ..."
(message varies depending on the dump software - yes, I'm doing this
from multiple machines/OSes/dump commands, each with different 
idiosyncrasies, arguments, etc...)

When I get the expect message, I call a sub to change tapes using the
tape robot.  That's the plan anyway.  :)

Glen

-- 
Glen Davison			gl...@ma...
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