Great! but what's the caret for?

>>I have to working using a constant as the second datetime but I cannot get datetime() to take a parameter.
>>I get a message saying too many parameters with the code below. I'm using vfp5.
>>
>>>>Is there a way to convert a datetime to a numeric value? Actually it needs to be negative but I can multiply by -1.
>>>
>>>subtract another datetime from the datetime
>>>
>>>lnCurrentTime = datetime() - datetime(1970, 1, 1) && equivalent to a C time_t
>
>-(datetime() - {^1970-1-1 0:0:0})
>
>or better
>
>#define BASE_DATE_TIME {^1970-1-1 0:0:0}
>
>-(datetime() - BASE_DATE_TIME)