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From: j@uriah.heep.sax.de (J Wunsch)
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: Re: HELP, I need intel assembler and UNIX C porting help - I'm STUCK! ):
Date: 23 Feb 1997 02:02:43 GMT
Organization: Private BSD site, Dresden
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References: <squishE5xo2n.M2y@netcom.com>
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squish@netcom.com (Michael Almquist) wrote:
> The program compiles FINE but when I run it I get:
> Program received signal SIGBUS (10), Bus error
> 0x178c in __outb (port=100, data=254 '~') at /usr/include/machine/pio.h:149
> 149 __asm __volatile("outb %0,%%dx" : : "a" (data), "d" (port));
>
> Every single little program I write "outb (0xd6, 0xc1);" "outb(0x60,0xFF);"
> etc crashes with the same error.
Of course. Normal user programs aren't allowed to perform direct port
IO. This is an access violation, and the kernel maps it into SIGBUS.
I don't know for NetBSD, but for FreeBSD, the backdoor is to keep a
descriptor on /dev/io open, in order to get IO port privileges.
The correct style however is to write a kernel driver that does the
actualy IO.
--
cheers, J"org
joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)