[Lazarus] DateDif function needed

[John Landmesser]

Hi List,

i'm searching a pascal datetime function that simulates an Excel 
function: "DateDif"

Excel for example knows the function DateDif that returns the number of 
Years, month and days between Date1 and date2.

Date1 := 21.12.2012
Date2 := 01.01.2013

Result would be: 0 years, 0 moths, 11 days

I tried to do it on my own, but without success.

But i think there is a function out there but i don't know its name :-((

Thanks for your tipps

John