Date: Wed, 24 Apr 1996 08:57:38 +0200 (MET DST)
From: "Christoph P. Kukulies" <kuku AT gilberto DOT physik DOT rwth-aachen DOT de>
Subject: Re: Odd printf behaviour
In-reply-to: <Pine.LNX.3.91.960423221544.1326A-100000@abigail.eee.upd.edu.ph>
To: orly AT abigail DOT eee DOT upd DOT edu DOT ph (Orlando Andico)
Cc: gfedor AT lerc DOT nasa DOT gov, djgpp AT delorie DOT com
Reply-to: Christoph Kukulies <kuku AT gilberto DOT physik DOT rwth-aachen DOT de>
Message-id: <199604240657.IAA02595@gilberto.physik.rwth-aachen.de>
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> 
> On 23 Apr 1996, Gregory Fedor wrote:
> 
> > I wrote some simple code that utilizes the gotoxy() and printf() 
> > statements to place text on the screen, ala:
> > 
> > 	while(!done)
> > 	{
> > 		gotoxy(column, line);
> > 		printf(" %... ", ...);

                fflush(stdout);

or

    put a setvbuf(stdout,NULL,_IONBF,0);

at the beginning of your file.
(not sure if if works under djgpp, though).



> > 
> > 		// update column
> > 		// update line
> > 	}
> > 
> > When I run this type of code nothing appears on the screen.  I can see 
> > the cursor jumping around, but nothing else.  However, if I include a 
> > '\n' in the printf statement, things display fine, *or* as soon as I 
> > printf with a '\n' outside the loop, then **all** the text gets 
> > displayed.  It's almost as if it's being buffered, and isn't displayed 
> > until a '\n' comes along.
> > 
> > I'm stumped, anyone got a hint?
> > 
> > Thanks
> > Gregory
> > 
> > -------------------------------------------------------------------------------
> > Gregory A. Fedor                          ADF Inc. / NASA Lewis Research Center
> > Computer Engineer                               Microgravity Experiments
> >     work: gfedor AT lerc DOT nasa DOT gov  http://sven.lerc.nasa.gov/~gfedor (216)977-1247
> > personal: gfedor AT en DOT com         http://www.en.com/users/gfedor
> > 
> 
> if i remember the bad old days of turbo c well enough, printf() which is 
> a stream io command and gotoxy() which is a console io command don't mix, 
> so the things you see are probably just a fluke. also, djgpp buffers 
> stdio with a 4k buffer (i think) which adds more complexity. i believe 
> what you should do is use curses (there's one for djgpp) and avoid the 
> nonportability of the turbo c conio.h functions.
> 
> 
> 

--Chris Christoph P. U. Kukulies kuku AT gil DOT physik DOT rwth-aachen DOT de