Validate date format in a shell script

Question

I have to create a Shell Script wherein one of the parameters will be the date in the format dd/mm/yyyy. My question is, how can I check if the Date passed as parameter real

Answer 1

How about using awk:

echo "31/12/1999" | awk  -F '/' '{ print ($1 <= 31 && $2 <= 12 && match($3, /^[1-9][1-9][1-9][1-9]$/)) ? "good" : "bad" }'

It prints "good" if its valid date else prints "bad"