Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!samsung!umich!sharkey!tygra!dave
From: dave@tygra.ddmi.com (David Conrad)
Newsgroups: comp.lang.pascal
Subject: Re: Preset KeyPressed Function?
Message-ID: <536@tygra.ddmi.com>
Date: 26 Nov 90 06:23:56 GMT
References: <9011251958.AA08961@euler.Berkeley.EDU> <1728@umriscc.isc.umr.edu>
Reply-To: dave@tygra.UUCP (David Conrad)
Organization: CAT-TALK Conferencing Network, Detroit, MI
Lines: 30

In article <1728@umriscc.isc.umr.edu> mcastle@mcs213a.cs.umr.edu (Mike Castle) writes:
>
>I was using  a    repeat until keypressed   routine at the ends of some 
>[...]
>Unfortunately, that doesn't clear the keyboard buffer.  Any subsequent
>keypressed call returned true.  Also, readkey would return that keystroke
>immediately.
>
>I've since gone to using  ch:=readkey  when ch is type ch and not used for
>anything else.
>

It can also be done without wasting an otherwise unused variable:
  ...
  repeat
    ...
  until keypressed;
  if readkey = #0 then if readkey = #0 then;
  ...
This method tosses out the second code returned by those keys which
return two codes (such as F1 and PgDn), an advantage over the above
method.  Hope this helps.
--
  David R. Conrad   | The goal of Artificial Intelligence is to build
dave@tygra.ddmi.com | computers which act like the ones in the movies.
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