% rm blah.txt
% perl -wE'use Tie::File;tie my @A, "Tie::File", "blah.txt", discipline => ":encoding(UTF-8)", recsep => "\r\n" or die $!; $A[2] = "Hallo";$A[4] = "Welt";'
% od -A n -c blah.txt
  \r  \n  \r  \n   H   a   l   l   o  \r  \n  \r  \n   W   e   l
   t  \r  \n