Binary package “datefudge” in ubuntu bionic
Fake the system date
This program (and preload library) fakes the system date so that
programs think the wall clock is ... different.
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The faking is not complete; timestamp on files are not affected in any
way.
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This package is useful if you want to test the date handling of your
programs without changing the system clock. Examples: Does it handle
expired certificates correctly? Does it work on a leap day?