SW>I know that it can be done in dos via file sharing, but I don't know how
SW>to do that, or if there is a better way.  I would like to stay in DOS if
SW>at all possible...as far as I know, most versions of Windows, OS/2, and
SW>even some unix have dos emulators.  Plus going to a multi-tasking system
SW>would mean I would need a library or something like it for the platform.
If you were to implement a file sharing system (such as for a chat) you would 
have to do the following :-
1) install dos's SHARE program.
2) install an isr that gets and displays input from user and if enter pressed
   a) write to the main file.
3) get and record the size of the main file
4) if size of file is bigger or smaller than recorded then
  a) read contents of the file and display them
4) goto 3
5) remove isr, clean up etc..
You could replace the file with a specific location in memory, but the file 
sharing system works fine.
bye for now..
... I've got a Mickey Mouse PC with a Goofy operating system.
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