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To: Michael Smith <msmith@atrad.adelaide.edu.au>
cc: ROBIN@ptnsct.nis.za (Robin Hunt), questions@freebsd.org
Subject: Re: Accessing i/o map space with freebsd 2.1.0 
In-reply-to: Your message of "Tue, 08 Aug 1995 23:40:48 +0930."
             <199508081410.XAA25745@genesis.atrad.adelaide.edu.au> 
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Date: Tue, 08 Aug 1995 10:16:32 -0500
From: "Eric L. Hernes" <erich@lodgenet.com>
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> Robin Hunt stands accused of saying:
> 
> > 2) If not, how can I use outb / inb without creating a bus error?
> 
> Your program must be run as root; before performing any I/O operations,
> open the file /dev/io.  This action grants the process priveledges to 
> read and write directly to the hardware.
> 
Does this really work?
in /usr/src/sys/i386/i386/mem.c, it looks like it is #ifdef'ed out.

at or about line 174:

#ifdef notyet
/* 386 I/O address space (/dev/ioport[bwl]) is a read/write access to seperate
   i/o device address bus, different than memory bus. Semantics here are
   very different than ordinary read/write, as if iov_len is a multiple
   an implied string move from a single port will be done. Note that lseek
   must be used to set the port number reliably. */


> > robin@ptnsct.nis.za
> 
> -- 
> ]] Mike Smith, Software Engineer        msmith@atrad.adelaide.edu.au    [[
> ]] Genesis Software                     genesis@atrad.adelaide.edu.au   [[
> ]] High-speed data acquisition and                                      [[
> ]] realtime instrument control          (ph/fax) +61-8-267-3039         [[
> ]] My car has "demand start" - Terry Lambert                            [[
> 

eric.

--
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