From:	hhkraemer AT web DOT de (Horst Kraemer)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: fflush (in djgpp)
Date:	Tue, 17 Apr 2001 18:33:48 GMT
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On Tue, 17 Apr 2001 16:59:54 +0200, Tim Van Holder
<tim DOT vanholder AT falconsoft DOT be> wrote:

> Michael Ahumibe wrote:
> > 
> > Can someone tell me what's wrong? or if there is a work around.
> 
> As said before fflush(stdin) isn't supposed to clear the input; I
> believe
> that's a Borlandism (or a Microsoftism, or both).
> 
> But IIRC you can use the '%*c' specifier to read any number of
> characters
> (effectively clearing the input), without placing them into memory.
> 
> So scanf ("%d%*c", &age) should read '20' into age and discard the rest.

No. Fortunately this isn't true. If %*c would mean "read any number of
characters" it would prompt eternally for input until EOF...

	%*c

would read and discard one character only because this syntax is
equivalent to %*1c. And the problem is that it would prompt for input
if no character is available. A correct procedure to throw trailing
input and leave the terminating \n in the stream is

        int test;
	test=scanf("%d", &age);
	scanf("%*[^\n]");
        /* throw anything beyond what could be read. Stop
           reading and throwing in front of \n */
        /* if test == 1 then the input line started with a valid int,
           otherwise age's value won't change */


Regards
Horst

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