countdown to christmas - Shell Programming and Scripting

kodak · #2 (**permalink**) 04-23-2009

Code:

#!/bin/sh
XMAS=`date -d "Dec 25" +%j`
TODAY=`date +%j`
DAYS=$(($XMAS - $TODAY))
if [[  ! $DAYS =~ ^[0-9+$ ]]; then
        echo There are $DAYS days left until Xmas.
else
        echo Merry Xmas and Happy New year\!
fi

This kind of cheats. If it's a negative number it assumes that it's after christmas and will just print the second line. you could do some more logic to make it return the actual number until the next christmas, but I didn't want to gum it up too much.