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A persistent object is an object that survives reboot.
On [[Unix]], files and directories are persistent but
processes and [[unix/file_descriptor]]s are not.  [[microkernel/EROS]] is
an example of an orthogonally persistent system:
processes and [[capabilities|capability]] also survive reboot.  To a
process, it generally only looks as if it had not been
scheduled for a long time; the rest of its environment
remains essentially the indistinguishable.


# GNU/Hurd

The GNU/Hurd is not a persistent system: there are no persistent
[[capabilities|capability]].  All data that is stored in files in the file
system, is serialized.


# Further Reading

[[!toggleable id=shapiro_capintro_1999 text="""[[!template id=note
text="*[[shapiro\_capintro\_1999|capability]]*:
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  * Section *Writing Things Down* in [[!toggle id=shapiro_capintro_1999
    text="[shapiro\_capintro\_1999]"]].


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