... systems¹

In fact it can be used on any system, which fits the requirements. See 3, for more information

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... need²

Have a look at the portability issue, 3.5, page .

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... location³

Have a look at the portability issue, 3.4, page .

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... Unix-system⁴

As of the current date tar seems not to be able to save ACLs (access control lists).

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... support⁵

Reiserfs, ext2, ext3, xfs should work fine, jfs is reported to had problems with some characters.

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... round⁶

Those systems are most likely not Unix-alike and have a general different design with complex and broken registries.

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... limit⁷

Please report if you ever reach this limit on a filesystem, I would be interested in how deep the limit is. Currently one person reported that after 125 subdirectories the limit is reached in the operating system with the blue screen.

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... variables⁸

Those which can either be TRUE or FALSE.

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