Question

I have several commands printing text to a file using perl. During these print commands I have an if statement which should delete the last 5 lines of the file I am currently writing to if the statement is true. The number of lines to delete will always be 5.

if ($exists == 0) {
  print(OUTPUT ???) # this should remove the last 5 lines
}

Answer 1

You can use Tie::File:

use Tie::File;
tie my @array, 'Tie::File', filename or die $!;

if ($exists == 0) {
    $#array -= 5;
}

You can use the same array when printing, but use push instead:

push @array, "line of text";