From: gfoot AT mc31 DOT merton DOT ox DOT ac DOT uk (George Foot)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Strange behaviour...
Date: 9 Mar 1997 01:46:17 GMT
Organization: Oxford University
Lines: 33
Message-ID: <5ft4p9$db2@news.ox.ac.uk>
References: <33219722 DOT 5A96 AT mbox DOT vol DOT it>
NNTP-Posting-Host: mc31.merton.ox.ac.uk
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Stefano Bizzi (sbcinf AT mbox DOT vol DOT it) wrote:
: I have a little problem compiling a simple program...
: With a code like this:

: ....
: printf("\nHello World");
: printf("\nSomething else...");
: clrscr();
: .....

: The compiler execute the clrscr() function BEFORE the last printf().
: Then, it writes "Hello World", it clear the screen and, then, write
: "Something else". Why? (I compiled the from RHide).

You are mixing commands from stdio.h and conio.h, which is generally
not a good idea. printf() sends to stdout, which is line buffered. This
means that nothing gets printed until you send a \n character. If you
stick to stdio.h routines, this isn't a problem because, for instance,
scanf() will clear the buffer before waiting for input. However, you
are using clrscr() which is a conio.h function, and so the buffer is 
not flushed.

You have two main options here:

1) Put fflush(stdout) before clrscr() to manually flush the buffer

2) Only use conio.h routines (i.e. use cprintf() instead of printf())

HTH

-- 
George Foot <gfoot AT mc31 DOT merton DOT ox DOT ac DOT uk>
Merton College, Oxford.