You'll need to use the waitfor and print (Net::Telnet) to process the initial menus. Something like this ...

$telnet->waitfor(Match => m{$last_line_of_the_1st_menu}smx);
$telnet->print(q{a});
$telnet->waitfor(Match => m{$last_line_of_the_2nd_menu}smx);
$telnet->print(q{b});
[download]

Thanks:-)

I forgot to mention that I was using Net::Telnet module. Now the problem is kind of fixed, but some wired problem just remain :-(

I use get to get the content of sub menu, and remove the telnet control sequences, then have the clean and tidy text manipulated.

The problem is that I can not use getline, or getlines, they offer nothing to me. And I can not use waitfor because the last several lines of the control menu are all same, so...

And also, I found that Net::Telnet may have some problem in dealing with TCP packets, sometime it just mis-treat a packet end as a EOF and return the incomplete content to me when there are still some packets to read. The timeout value is enough for it, I am sure.

Hi,

Normally, I use the waitfor to match a temporary changed "prompt", like a --more--. And, as you can read in the Net::Telnet with

($prematch, $match) = $obj->waitfor($matchop);
$obj->print(q{a}) if( $prematch =~ m{f\. Advanced}sm );
$obj->print(q{b}) if( $prematch =~ m{l\. Command Line}sm );
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you can use the $prematch to get the context.

Probably, your problem it's not with the TCP packets and the Net::Telnet, but with a premature match. Use the dump_log to inspect the flow of the session, and last, but not the least, use the perl -d to check each telnet interaction.