convcal(1) on Linux
The text 71f40cca4647, as Debian 6.0 (Squeeze), Debian 5.0 (Lenny), Debian 4.0 (Etch), Debian 3.1 (Sarge), Debian 3.0 (Woody) shipped it.
convert dates to different formats
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-h -
-i -
-o -
-r -
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