my $filename = "blah.txt"; #replace as needed
rename($filename, $filename . '.bak') 
    or die("Unable to rename $filename to $filename.bak: $!\n");
open(INFILE, $filename . '.bak') 
    or die("Can't open $filename.bak for input: $!\n");
open(OUTFILE, '>' . $filename) 
    or die("Can't open $filename for output: $!\n");
  my $linecount = 0;
  while ($line = <INFILE>) { 
    print(OUTFILE $line) if ($linecount);
    $linecount++;
  }
close(INFILE);
close(OUTFILE);