open (IN1, "<FA.vhd") or die;
open (OUT, ">common_modify.vhd") or die;

while (<IN1>) {
print OUT;
	if (/signal/){
	open (IN2, "<enabled_nets.txt") or die;
	my @enabled_nets = <IN2>;
	chomp @enabled_nets;
		while (<IN2>) {
			print OUT ; 
			print OUT ',enable_c,';
		}
	close (IN2);
	}
}
close (IN1);
close (OUT);