since its a webpage, am not able to see error/warning messages
If you add these lines to the top of your script it should display the error: 
print "Content-type: text/html\n\n";
use CGI::Carp('fatalsToBrowser');

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In reply to Re: how to call system commands from cgi file? by tangent
in thread how to call system commands from cgi file? by kpofcochin

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