storing return value from Expect

perlknight has asked for the wisdom of the Perl Monks concerning the following question:

All, I have an expect script which logs into a pix firewall and ping the vpn tunnel, how do I get an output from this:

 $ssh->expect(10,
                        [ qr 'wall#',
                        sub {
                                $ssh->send("ping 172.16.10.29\n"); # h
+ow do I get the output of this ping into a variable?
                        }],

                );
[download]

I've tried my $bla = $ssh->send("ping 172.16.10.29\n") but it doesn't work. Any idea? thanks.

Comment on storing return value from Expect Download Code

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Re: storing return value from Expect by belkajm (Beadle) on Aug 09, 2002 at 03:00 UTC
I wasn't able to get it to work using the calling-syntax you were using, which is a pity, as I think is the neatest way to call expect. Anyway, here is what I came up with as a possibility: `$ssh->expect(10, '-re', 'wall#'); $ssh->send("ping 172.16.10.29\n"); $ssh->expect(10,"\n"); $ssh->expect(1); $bla = $ssh->before();` [download] Note that the second expect line is only required if echo is on. Even if it is, you can miss out the line if you don't mind grabbing the ping command as part of $bla. The timeout value in the last expect line should be set based on how long the ping will take. Hope this is helpful, Yoda	[reply] [d/l]
Re: storing return value from Expect by thor (Priest) on Aug 09, 2002 at 11:44 UTC
You want to store the value from your `expect`, not the `send`. The following is untested: `$ssh->send("ping 172.16.10.29\r"); #notice \r here; I think it's prefe +rred over \n in expect my $stuff = $ssh->expect(10, qr 'wall#');` [download] If this doesn't work, a perldoc Expect might be in order. thor	[reply] [d/l] [select]
Re: Re: storing return value from Expect by belkajm (Beadle) on Aug 09, 2002 at 18:20 UTC
unfortunately, expect doesn't work this way. according to the docs on sourceforge: If called in a scalar context, expect() will return the position of the matched pattern within $match_patterns, or undef if no pattern was matched. This is a position starting from 1, so if you want to know which of an array of @matched_patterns matched you should subtract one from the return value. If called in an array context expect() will return ($matched_pattern_position, $error, $successfully_matching_string, $before_match, and $after_match). Also, please note that \r might not work with some programs when raw mode is activated. Normally expect does cr->lf translation, but this is disabled in raw mode. From a brief read of the docs, i think they are suggesting that \n is actually the better choice.	[reply]