Xref: utzoo alt.msdos.programmer:812 comp.sys.ibm.pc:39252
Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!ucbvax!bloom-beacon!eru!luth!sunic!tut!hydra!hylka!teittinen
From: TEITTINEN@cc.helsinki.fi (Marko)
Newsgroups: alt.msdos.programmer,comp.sys.ibm.pc
Subject: Re: i/o routines and non-standard video modes
Message-ID: <1494@cc.helsinki.fi>
Date: 4 Dec 89 02:31:16 GMT
References: <2090@calvin.EE.CORNELL.EDU> <2980@einstein.ptolemy.arc.nasa.gov> <2092@calvin.EE.CORNELL.EDU> <2544@alva.tut.fi> <89320.130954CMH117@PSUVM.BITNET>
Organization: University of Helsinki
Lines: 17

In article <89320.130954CMH117@PSUVM.BITNET>, CMH117@PSUVM.BITNET (Charles Hannum) writes:
> DOS (not necessarily BIOS) is hard-coded
> to work with only the first 25 lines of the screen.  The problem here is that
> to do anything else, DOS would have to automagically sense the current screen
> size, which, since it uses BIOS calls, would tremendously slow down screen
> I/O.

I don't think screen handling is terribly slow in DOS 4.0, but it knows
whether the screen is in 80*25 or 80*50 line mode. Easy to use (command
is "mode ,50", but too few programs check whether they are running on
80*25 or 80*50 line screen. Of course, all DOS programs do it,
especially more.

-- 
E-Mail: teittinen@finuh.bitnet               ! "Studying is the only way
        teittinen@cc.helsinki.fi             !  to do nothing without
Marko Teittinen, student of computer science !  anyone blaming you" -me