Date: Thu, 1 Sep 1994 09:26:50 +0500
From: ronis AT onsager DOT chem DOT mcgill DOT ca (David Ronis)
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: bug in scanf()

There is a bug in scanf() in version 1.11.m5.  The following code shows
the problem:

#include <stdio.h>

main()
{
	while(1)
	{
		int i,j;
		j=scanf("%d",&i);
		printf("i=%d; j=%d\n",i,j);
	}
}

As long as the field scanned is a valid integer, things work as
expected. However, if an invalid integer is entered, e.g., a character,
scanf returns 0 and leaves i untouched (this is as expected).  The
problem is that on the next loop scanf no longer reads the console.  It
simply returns zero without reading any input.


David Ronis