Message-Id: <199810010003.UAA21645@delorie.com>
Comments: Authenticated sender is <mert0407 AT sable DOT ox DOT ac DOT uk>
From: "George Foot" <george DOT foot AT merton DOT ox DOT ac DOT uk>
To: allen DOT asjp AT cableol DOT co DOT uk
Date: Thu, 1 Oct 1998 01:01:14 +0000
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Subject: Re: Strange DJGPP bug
Reply-to: mert0407 AT sable DOT ox DOT ac DOT uk
CC: djgpp AT delorie DOT com
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On 30 Sep 98 at 18:40, Peter Allen wrote:

> Test User wrote:
> > 
> > On Sun, 27 Sep 1998, Peter Allen wrote:
> > 
> > >Test User wrote:
> > 
> > >> Here's a short C program:
> > 
> > >> #include <stdio.h>
> > >>
> > >> int main()
> > >> {
> > >>         char buffer[256];
> > >>
> > >>         printf("Input: ");
> > >>         fgets(buffer, 255, stdin);
> > >>         printf("\nYou typed %s\n");
> > >> }
> > 
> > >> When compiled with the Linux version of GCC, this program
> > >> prints an Input: prompt. When the user types something and
> > >> presses ENTER, it then prints the string the user typed,
> > >> in the form of "\nYou typed %s\n", where \n is a newline and
> > >> %s is the string the user typed, including the trailing newline.
> > >>
> > >> When compiled with DJGPP, the program just sits there until
> > >> the user types something and presses ENTER. Then, the
> > >> program spews out the Input: prompt and the string the
> > >> user typed at the same time. For some reason, it executes
> > >> fgets() first, and then executes both printf's together. You
> > >> can't get it to print the prompt first, then call fgets(),
> > >> and then print the results. You can substitute fgets() for
> > >> your own elaborate loop system. You'll get the same result.
> > 
> > >To save time switching between protected mode and dos, djgpp is
> > >buffered, so the easiest way to make it print something on the
> > >screen is to add \n to the end of printf ("input:") line.
> > 
> > >               Peter Allen
> > 
> > That would look pretty strange. Imagine an FTP program that does
> > this. The prompt would be on one line, and the command on a different
> > line. How did they get BASH to work? It doesn't print "bash-2.01$ "
> > and then have the user type the commands on the next line. Both
> > the prompt and the user's input are on the same line.
> 
> Woops, sorry.  I forgot to say you could put fflush(stdout); at the end
> instead.  Sorry

The buffer should be automatically flushed when you take input 
from stdin, so the code snippet above should work -- the text 
should be printed before the input is taken.  It works fine on 
my machine, anyway.

-- 
george DOT foot AT merton DOT oxford DOT ac DOT uk