Here's a solution using Tie::File:

use Tie::File;

tie @array, ’Tie::File’, "filename" or die "tie failed: $!";

# remove the first 100 lines:
splice(@array, 0, 100);

untie @array;
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If you don't know the exact line number, then you could do something like this:

tie @array, 'Tie::File', "filename" or die ...;
my $i;
for (@array) {
  if (m/some regex/) { last }
  $i++;
}
splice(@array, 0, $i);
[download]