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0 pointsAdmiralAsshat8y ago0 comments

I expect that they should preserve the ownership and permissions of the original file if I tell it to.

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7 comments · 2 top-level

rakoo8y ago· 5 in thread

How can it have the same owner if it's a different machine, and users aren't the same ?

Do tarballs store the user/group names as strings or do they store the uid/gid instead?

It is one of the goofy things about Unix systems is most tools speak uid/gid and woah is you if two machines on the network have “bob” only as different uid’s.

Not entirely sure if windows has the same problem as to be honest if you use active directory most of that stuff is auto-magic.

My hunch is that going with the ID vs. the “friendly name” has a bunch of trade offs and whichever you pick will come with serious drawbacks.

fapjacks8y ago

Heh I think you meant "woe is you" although what you've got is actually rather delightful.

justincormack8y ago

They can do either - traditional tar formats have uid as a number, but the newer pax format has both numeric and named values.

1 more reply

saulrh8y ago

I feel you're on the right track with that hunch - Zooko's triangle should apply in some way.

icholy8y ago

Magic ... obviously

jolmg8y ago

How can a normal user create files owned by another user? If tar allowed that, you could write any file with any permission and any ownership anywhere by first crafting a tar file of those files and then extracting them. It'd render the file permissions and ownership system completely moot.

EDIT: To get the effect you want, run tar as root. That's required to ensure you have the permission to override the DAC system, first.

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