Using: 

open(FILE, "<some_file.txt");
while(<FILE>) {
  ## Do some processing...
}
close(FILE);

[download]

I can read a file line-by-line from the top down. How would I go about reading it line-by-line from the bottom up?

Under Linux I suppose it would be fairly easy to have my code read standard input and simply tac (like cat, but in reverse) the file into the script. However, I can't guarantee that tac will be available on all systems where this code will run and would therefore prefer to do it with Perl.

The file in question is large (~600Mb) so I'd rather not read it into memory first :)

Any ideas?

In reply to Reading a file line-by-line from the bottom up by fx

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