I want to know how my given code is working for you?
Uhm, I cut-and-pasted your code, changed the filenames and ran it from the command line?
Else tell me how to pass a perl variable value to Unix command?
I don't understand. Your initial post starts with: 
$a=`dd if=/dev/$cmd of=/dev/null bs=4096 count=2 > ddlog.txt 2>&1`;

[download]
which passes a variable to the command. But what has that to do with drop down lists, or printing to terminals?

In reply to Re^5: Adding DD Unix command in Perl by JavaFan
in thread Adding DD Unix command in Perl by asha_mail

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