Hi gurus,

I have been using Perl Telnet module to log into Cisco router to paste in the command, as below, which works fine. In example below, you can see that long command such as "rate-limit input..." has been truncated and a dollar sign ($) appeared indicating that the terminal display for this command has been contracted.

Now I am trying to give it a web interface - invoking the same Perl script. It works but the display from the web is garbled and looks very messy. See example further below.

After close check, I found out those un-printable characters are actually "Back Space", corresponding to ASCII value 008. My interpretation is that while a line getting too long, the terminal issue certain number of "Back Space" to delete excessive characters which could not hold in one line. I counted the number of characters hidden, which is the same as the number of Back Space.

My question (and wish) is to present the output nicer on webpage. There are several challenges for me: 1. snippets of the long command have been echoed back multiple times, interleaved by "Back Spaces". These snippets are overlapping, and some whole word has been broken up by white space or Back Space. 2. If I only keep latter, say 60 characters, as an easier approach, I would lose prompt, such as R1(config-subif)#, which is anchored at begging of the line; 3. my idea is check the output, each time I encounter a Back Space, I go backwards to delete same number of characters, which seems a bit hard to implement.

Any input are appreciated. -- Jun

Below are display from terminal, which show contracted format for long command:

Do you want to proceed with router config?
Input "y" to proceed, or "n" to abort
y
yThe file is:temp_config
The router is 150.1.1.1
R1#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
R1(config)#interface FastEthernet0/1.30
R1(config-subif)# bandwidth 10000
R1(config-subif)# encapsulation dot1Q 30
R1(config-subif)# ip address 10.248.223.85 255.255.255.252
R1(config-subif)# no ip redirects
R1(config-subif)# no ip unreachables
R1(config-subif)# no ip proxy-arp
R1(config-subif)# no snmp trap link-status
R1(config-subif)# no cdp enable
R1(config-subif)# no shutdown
R1(config-subif)#$0 conform-action set-prec-transmit 1 exceed-action d
+rop
R1(config-subif)#$0000 3840000 conform-action transmit exceed-action d
+rop
R1(config-subif)#end
[download]

Below are display from Web for output from the same Perl script, which shows garbled characters (which actually are Back Spaces, ASCII 008):

R1#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
R1(config)#interface FastEthernet0/1.30
R1(config-subif)# bandwidth 10000
R1(config-subif)# encapsulation dot1Q 30
R1(config-subif)# ip address 10.248.223.85 255.255.255.252
R1(config-subif)# no ip redirects
R1(config-subif)# no ip unreachables
R1(config-subif)# no ip proxy-arp
R1(config-subif)# no snmp trap link-status
R1(config-subif)# no cdp enable
R1(config-subif)# no shutdown
R1(config-subif)# rate-limit input 10240000 1920000 3840000 conform-ac
+tion se$ 
+input 10240000 1920000 3840000 conform-action set         -p
+rec-tra400
+00 1920000 3840000 conform-action set-prec-tran         smit
+ 1 ex000 3
+840000 conform-action set-prec-transmit 1 exc         eed-ac
+tio conform
+-action set-prec-transmit 1 exceed-action          drop
R1(config-subif)# rate-limit output 10240000 1920000 3840000 conform-a
+ction t$ 
+output 10240000 1920000 3840000 conform-action tr         an
+smit ex240
+000 1920000 3840000 conform-action transmit exc         eed-
+actio0000 
+3840000 conform-action transmit exceed-action          drop
R1(config-subif)# end
[download]

A bit of code snippet just for completeness.

       $session->login('user', 'cisco');
       $session->enable("cisco123");
       # feed in command file line-by-line
       while (<$tmp_fh>) { 
            my @output = $session->cmd("$_");   
            print @output;              
           };
       $session->close;
[download]