a,b,c,d,e,f,g
1,2,3,4,5,6,7
x,y,z,s,t,u,v

##</code><code>##

$id = 1
open(MYFILE,"/var/tmp/mylist.dat") or die "Cant open mylist.dat"

while (<DMPLD>) {
      chomp;
      die "Request Id $id already present in file\n" if $_ eq $id;
                }

close DMPLD;