This is one of those things I've done before and the basics seem simple, but I must be screwing up on something obvious. I've been over the docs on CPAN a number of times. I've used Expect to read from a modem and, years ago, to control a process. Now it won't work for me at all.

I'm testing it on telnet, where I telnet to a system I have set up that doesn't need a username or password, use 'ls', then log out, and even that is not working.

Here's my code:

#!/usr/bin/perl

    use Expect;

    our $abi;

    $res = open_telnet();
    if ($res) {
        print "Failure.  Error message: $res\n";
        exit;
    }
    telnetcmd("ls");
    telnetcmd("exit");
    exit;

sub open_telnet {
    my ($cmd, $res, $before, @parm);
    $cmd = "telnet wogglebug";
    $abi = Expect->new();
    $abi = Expect->spawn($cmd) or die "Can't do expect'";
    $res = $abi->expect(5, "/ #", "not known");
    if ($res == 1) {
        return 0;
    }
    $before = $abi->before();
    if (!$before) {
        $before = "telnet failed.  No reason given";
    }
    return $before;
}

sub telnetcmd {
    my ($cmd, $res);
    $cmd = shift(@_);
#    print $abi "$cmd\n" or die "Can't write to expect object";
    $abi->send("$cmd\n") or die "Can't send to expect object: $abi->er
+ror()";
    $res = $abi->after();
    print "-----------\nAfter: $res\n----------\n";
    return $res;
}

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If I run this as it is, then I always get an error on the 4th line of the telnetcmd routine: "Can't send to expect object: Expect=GLOB(0x8eb92e8)->error() at /threshNet/bin/xm-test line 41." Okay, the obvious is to just use the line before it, the commented out one that prints the command to the process, but even when I do that, I don't get output from the process, either by watching it as it runs, or by using expect->after().

This is just testing, I'm working on controlling another program with Expect, and it seemed to need to use Expect->send_slow() to send commands to that program, so I feel I'll need send() or send_slow() to make it work. But it seems like I must be doing something so obvious I can't find the problem.

There are also a number of other calls to the Expect object that I can't get to work. Expect->pid() doesn't return anything. Except->clear_accum() won't clear the data already in the buffer and Except->before() always returns the data from my first Except->before() call, no matter how many times I've called it.

Any help is appreciated. I suspect once someone points out what I did wrong, I'll be doing a *facedesk* in disbelief I missed something I should have known.

In reply to Expect Issues by HalNineThousand

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