assigncrt 
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 assigncrt

Greetings

What's the purpose of this command if there is no i/o redirection?
It is said that assigncrt assigns a text file to the crt window.
Useing assigncrt (f); rewrite (f); you can write to the text file f
and to the crt window at the same time, that's how i understand it.
But the question is how can you read that file later?
I did the following:

assigncrt (f);
rewrite (f);
writeln (f,'something');
reset (f);
readln (f,s);

Instead of reading the string s from previously writen textfile f, it
writes parallel to the crtwindow and to the string s. That is it
inputs just like a normal readln (s); would do.

Anyway i got an idea that i may be able to read the contents of the
crt window into a text file, and after that restore that text file
into the crt window, normaly inbetween i intendet to have some other
text in the same crt window.
In other words i wanna avoid direct reading from the VGA, when doing
windowflipping (similar to pageflipping), and only useing the CRT unit
so that the code will work on every machine that has a CRT specific
unif. I don't wanna know how that CRT works on Linux or Amiga, but it
only matters that it works.

I did not found a procedure that reads the char and the attribute on
curent cursor position in the CRT unit. Although a CopyCRTWindow
(bufr); procedure would be nicer and a RestoreCRTWindow (bufr); too.

I hope i will not be forced to use int $10, or even worse direct
memmory VGA load/store. During my work on the menues i moved from one
end to another in ways of text->screen output. 1st a unit based on
system calls then only useing CRT, for more portability and now back.
:(

Vasko



Tue, 25 Oct 2005 20:38:32 GMT  
 
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