#!/usr/bin/perl
use strcit;
use warnings;
use Tie::File;

my $file=$ARGV[0] or die("No File defined!\n");

tie( my @data, 'Tie::File', $file ) or die "Can't open $file ($!)\n";

for my $pos ( reverse (0..$#data) )
{
  if($pos>0 and $data[$pos]=~/<SUCHSTRING>/)
  {
    $data[$pos-1]=~s/.\n/\n/;
    splice(@data,$pos,1);
  }
}

print join('',@data);

untie(@data);