Something like this? 
use File::Slurp;
my $file_content = File::Slurp::read_file('file');
$file_content = reverse $file_content;
my $memory_file = \$file_content;
open my $memfh, '<', $memory_file or die "$!\n";

#...seek
#...read

close $memfh;

[download]
For details see these articles from the FAQ:
read-in-an-entire-file-all-at-once and
open-a-filehandle-to-a-string

In reply to Re: Best way to read a file into memory and use normal operation on memory file? by hexcoder
in thread Best way to read a file into memory and use normal operation on memory file? by james28909

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