Trial software and registering

[Cubist at aol.com]

sez jamesjrichards at lineone.net:
>On 21 Mar, 2005, at 09:30:01 -0500, Frank D. Engel, Jr. wrote:
>
>> When the app starts up, store the current time and date.  Then the next
>> time the app starts up, compare the current time and date with the one
>> you stored.  If the current time and date is before the stored one,
>> chances are someone is trying to trick the software.
>
>I have either an occasional system bug, or a dud battery in my Mac 
>which keeps resetting the system date to some time in 1970.  
>Contrariwise in the year or two approaching 2000 a number of people put
>their computer clocks forward to see what the fabled millennium bug 
>might do to them.  Also every year the system clock gets reset twice 
>for daylight saving, and I have been known to be working in PM when it
>should be AM.  In any of those circumstances ordinary human error or 
>computer failure might lead to an incorrect clock setting.  A system 
>clock check is inherently unreliable.
   Which is another reason to do something like my "count the number of 
minutes it's been used" protocol -- that way, you don't have to *care* about 
mis-set clocks, Daylight Savings, PRAM batteries, etc etc ad nauseum. Simple is 
good; code you don't have to write in order to detect/correct for an error, is 
code that can never have any bugs in it...