[fpc-pascal] strange behaviour of readkey...or not

[Florian Klaempfl]

Darius Blaszijk wrote:

> Hi there,
> 
> I have a console app that reads keys being pressed and then does some
> action. In short it would be like this:
> 
> repeat
>   if fileage(myfile) <> imyfile then
>   begin
>     writeln('file changed');
>     imyfile := fileage(myfile);
>   end;
> 
>   ch := readkey;
> until ch = 'q'
> 
> So what I want is that the fileage test is done continously and when a user
> presses a key some other procedure is executed. But the problem is that when
> "ch := readkey" is reached, the app seems to stay waiting until a key is
> pressed. In other words it only does the fileage test when I press a key
> other than q. In my example the fileage test is only done once.
> 
> Am I under the wrong impression that I should pull it off using readkey??
> What is the alternative??

Do check of keypressed first:
http://www.freepascal.org/docs-html/rtl/crt/keypressed.html