Determining actual elapsed (wall-clock) time

[Peter Hansen]

Roy Smith wrote:
> Peter Hansen <peter at engcorp.com> wrote:
> If you get the UTC time, daylight savings time doesn't enter the equation.  

Of course... I didn't think of that approach.  I don't actually care 
about absolute time, so this should work fine for at least the DST case.

> If you care about time, you want your system clock controlled by NTP.  
> There's just no excuse not to.

I guess as long as the NTP client is set up to ensure the time 
adjustments are smaller than some value X, it would be acceptable.  I'll 
have to look into how to set up Windows XP to prevent users from 
changing the time on their own, assuming that's possible.

> Is there some reason you can't just use the system clock?  

I was anticipating use of the system (running on Windows in this case) 
by users who might decide to change the time, and in certain cases that 
could cripple the software.  I hadn't thought of the possibility of 
simply preventing that, though if I insist on an NTP client being 
installed, they shouldn't have a problem with that.

Thanks for correcting my thought process...

-Peter