The previous revision was flawed in numerous ways:
- the if condition would depend on garbage stack values
- grdc(6) would loop n times, not n seconds. This only makes
a difference if it takes more than 1 second to recalculate/redraw
the display.
- style(9) violations
The following change adds argument checking and tracks the elapsed time
between loops explicitly and will exit after roughly n seconds.
While here sort headers and remove bogus #ifndef
Submitted by: bde
MFC after: 2 weeks
1c9d5fc21b