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

With some of my routers, when I log in, I don't get a username or password request, just the prompt. The problem is that cmd() matches against a prompt, so if you capture the output of cmd() directly after, it'll do it up to the prompt before. So you'll get whatever went on between the last two prompts, not the last one and the one directly after you issued the cmd.

Is there any way to fix this for certain instances? Like is there a 'cmd' count somewhere which can be bumped up by one by inserting a blank element or something?

toeslikefingers.com - because you've got too much time on your hands
  • Comment on Net::Telnet::Cisco: nullifying first prompt in output for cmd() matching

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Re: Net::Telnet::Cisco: nullifying first prompt in output for cmd() matching
by phydeauxarff (Priest) on Oct 23, 2003 at 14:08 UTC
    We had a similar issue using net::telnet for managing Netscreen devices.

    Fortunately, you can use the prompt method to account for pretty much whatever you want.

    Check out the docs for net::telnet::cisco as they contain a more exacting description of what the prompt method is expecting...you should be able to append to this to account for the behavior of your devices.

[reply]
      Actually, I don't think you can. From what I know, cmd() matches against the prompt. That's fine if the first time you see a prompt, it's been matched against a specific cmd or other call. What I'm talking about isn't the possibility of matching against a funky new prompt or something, which I kinda think is what you're suggesting. The problem I have is that there's a prompt which comes up *the second* I connect to the device. In other words, there's no way I can match against it and remove it from the buffered stream. And clearing the buffer doesn't beat that in my experience either. When you capture the output from a 'cmd()' the way it seems to work is that it reads the buffer of everything which has occurred in the telnet session so far. That buffer is matched against for every call made against the router, and every prompt is accordingly dealt with. So if you have a prompt appearing anywhere in the stream and it's not been matched, then all of your matched output will be one prompt behind. Sorry if you're dead right and I've missed it, but I can't see what the prompt documentation provides for other than matching against a given string.
      toeslikefingers.com - because you've got too much time on your hands
[reply]
        $session->waitfor_pause(1) may be a workaround. /chAlx
[reply]
[d/l]

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