GD> I've never used volatile on any direct screen I/O.  Perhaps
 GD> that's because under single-tasking DOS that's not a problem.
 EW> It would be a problem if your compiler optimized better, all screen
 EW> output could be removed, since you didn't tell the compiler that is
 EW> was volatile. volatile can also mean that other processes are
 EW> influenced by the values your program puts there, just as it can mean
 EW> that other processes may influence your program by putting values
 EW> there. ;-)
I don't understand why all screen output would be removed due to
optimization.  Can you explain, please?
Gerry Danen (gdanen@accessweb.com) C+Net BBS @ 403-477-9545
            http://www.geocities.com/SiliconValley/Way/9823
2 years, 142 days, 2 hours, 22 minutes, and 48 seconds until January 1, 2000.
... Acting without thinking is like shooting without aiming.
--- Maximus 3.01
---------------