[Canada]

I don't know why HN disallows reply in certain circumstances. If you replied to the original post I never would have seen your reply.

If you don't care if the third party can modify your data, then OK. If you did care though, does this checksum stop "tar xvzf foo.tgz" from writing modified data immediately? Or does it just tell you at the end?

[scottpiper]

Probably just at the end. My goal is disaster recovery (AWS disappears as a service to the world because an Amazon employee accidentally `rm -rf` everything, or my own admin `rm -rf`'s my account on accident) so for those situations, I'm going to need to extract out the data somewhere and then rebuild, so checking at the end of the extraction and unzip is fine for my needs.