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Date: Mon, 15 Jan 1996 14:39:44 -0500 (EST)
From: Sujal Patel <smpatel@wam.umd.edu>
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To: Scott Whittle <scott@patton.com>
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Subject: Re: Request examples of using outb() in inb()in program.
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On Mon, 15 Jan 1996, Scott Whittle wrote:

> I recently saw a thread on I/O at the port level using outb() and inb().
> Would someone post (or email) some source showing the use of each.
> 
> I wrote a small program, which complied fine, but when I ran it (as root)
> it puked big time.  I'm not into the frustration thing, so I figure I'd ask
> those who know. :)

You need to open /dev/io before you access the ports (O_RDONLY is rnough 
to read and write any port).  You can also use the KDENABIO ioctl on  
/dev/console (probably the preferred way, but /dev/io is easier :)


Sujal