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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: Ada Tasks and Keyboard I/O
Date: 1997/06/14
Message-ID: <dewar.866308778@merv>#1/1
X-Deja-AN: 248381238
References: <33A12825.1C80@onlink.net> <1997Jun14.081514.1@eisner>
Organization: New York University
Newsgroups: comp.lang.ada
Date: 1997-06-14T00:00:00+00:00
List-Id: <comp.lang.ada>


Larry said

<<Your program must be doing what the operating system views as
asynchronous I/O, so if you insist on DOS it may be that you
must use an add-on OS extender that makes it behave less like
DOS.  Some Ada compilers come with such extenders.
 >>


It requires nothing this heavy to implement this "properly" on DOS for
the special case of keyboard IO, which is the case you really want handled.
For examle, on the Alsys compilers for DOS, keyboard I/O was always handled
by a polling technique something like

   loop
      delay epsilon;
      if keyboard data present
          read it
          exit
      end if;
   end loop;

and you can manually program this if you want, by callng the appropriate
Int 21 routines.