If it done right, it should be faster than this buggy code you show here. I say buggy since you're assuming the input file is a multiple of 8 bytes.

Using IO::File is probably much slower than using read and write. Objects are slower than their non-object equivalent.

If you want to use sysread and syswrite, you can use them with the solution in Re: Fast parsing for cypher block chaining, which is what you should be using.

In reply to Re^5: Fast parsing for cypher block chaining by ikegami
in thread Fast parsing for cypher block chaining by fluffyvoidwarrior

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