in reply to need help to connect switch 192.168.1.2 using perl script.
I see "show running-config" and assume you mean a Cisco switch. If that's right, Net::Telnet::Cisco is a great place to start.
If you don't want to reinvent the wheel and can deal with a script that does A LOT MORE than just Telnet to Cisco switches, have a look at (shameless plug) Cisco Router Action Performing Perl Script
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