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From: jim@tiamat.fsc.com (Jim O'Connor)
Newsgroups: comp.unix.xenix
Subject: Re: system lockup
Summary: something doesn't look right here
Keywords: bug?
Message-ID: <387@tiamat.fsc.com>
Date: 15 Feb 89 15:42:46 GMT
References: <60@estinc.UUCP>
Organization: Filtration Sciences Corp., Chattanooga, TN
Lines: 32

In article <60@estinc.UUCP>, fnf@estinc.UUCP (Fred Fish) writes:
> 
> I had a case of a program running on a Bell Technologies MPE386,
> under SCO 386 Xenix Version 2.3.1, which was causing the system
> to lock up (no response to any typing on any terminal).  I finally
> tracked it down.  This simple program demonstrates the problem
> on my system:
> 
> 	static char buf [1024 * 1024];
> 
> 	main ()
> 	{
> 		write (0, buf, sizeof (buf));
> 	}

Something doesn't look right here.  Isn't this an attempt to write to
"stdin" which is probably not open for writing?  It seems that a return
value of -1, and errno set to EBADF should be expected.  As to why it 
hangs the system, I don't know, but it really shouldn't matter, since I
don't think too many programs would be intentionally writing 1024 * 1024 NULL
bytes to a file desciptor for which an attempt at opening for writing
(and in this case, closing one that is already open for reading) has not been
made.  

What program do you have that needs to do this?


------------- 
James B. O'Connor			jim@tiamat.fsc.com
Filtration Sciences Corporation		615/821-4022 x. 651

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