🚀 go-pugleaf

Gregory L Hansen (ghansen@isc.sjsu.edu) wrote:
: No matter what OS you're using, you'll have to poll sometimes to look for 
: things like key presses, switching the program to background or 
: foreground, quit and pause commands, things like that.  Even if it's a 
: straight read-data, calculate, save-date, you want the option of quitting 
: in the middle of it.  So somewhere at the bottom of your loop place a 
: polling call, and your WaitNextEvent and event handler can be included 
: in the OS-specific file.

The things you describe don't need polling, say under Unix. You can quit
most programs by typing a special key (normally ctrl-c) in most shells.
If the program runs in the background you use the kill command. All of this
is handled by the OS and shell. The programmer needs not take care about
that in his program.

I have done some programming in the Unix environment and didn't normally use
any polling, because it's not needed.

: And I suppose someone will come up with an example or two where that 
: hasn't been done but the program still works fine in the operating 
: system of their choice or for the task at hand.  To that, I can only 
: suggest that if you can write OS-specific code, you can find someplace to 
: call your polling function.

The point is that for a straight read-data, calculate, save-date program that
isn't OS-specific in the least you don't need polling or anything else and
are still able to stop your program switch between background or foreground
or assign a different priority to it under Unix.

Markus