Karol Baraniecki 190a6650bd cal: Add the -y option to show the current year ...

Without `-y`, to show the current full year you'd have to specify which
one: `cal 2023`. Adding `-y` makes it possible to see the full current
year without remembering what year we are in.

This option is also stolen from FreeBSD :^)

Additionally, validate args: prevent passing both -3 and -y at the
same time. Passing both `--three-month-mode` and `--year` to `cal`
doesn't make sense. You'd either want the one or the other.

2023-04-25 01:54:53 -06:00

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cal: Add the -y option to show the current year

2023-04-25 01:54:53 -06:00