Have you tried littering the above code with tracing commands to see what is being received from the box you're connecting to? Sometimes you need to initiate a telnet connection with a "\n" just to kick it into life and send a prompt.

e.g.

my ( $r, $resp );

# kick the connection into life with a carriage return
print $sock "\n";

# read in from the connection
while (sysread($sock, $r, 1024) >= 1) {
    print( STDERR 
           "At " . scalar(localtime(time())) 
           . " received '$r'\n" );

    $resp .= $r;
    $resp =~ /prompt>/ and last;
}

# print username to socket
print( STDERR "Sending username..\n" );
print $sock "$username\n";

# debugging loop just to see what we're getting
while (sysread($sock, $r, 1024) >= 1) {
    print( STDERR 
           "At " . scalar(localtime(time())) 
           . " received '$r'\n" );

    $resp .= $r;
}

[download]

Note you can use the strace command as the root user on a linux box to attach tracing to your script. It will give you an idea of what text is coming and going from your socket. Very useful for debugging.

In reply to Re^3: Logging into telnet using a socket by monarch
in thread Logging into telnet using a socket by mikeock

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