Re: LINUX is obsolete
[Prev][Next][Index][Thread]
Re: LINUX is obsolete
-
Subject: Re: LINUX is obsolete
-
From: ts@cup.portal.com (Tim W Smith)
-
Date: 7 Feb 92 01:30:59 GMT
-
Newsgroups: comp.os.minix
-
Organization: The Portal System (TM)
Andy Tanenbaum (ast@cs.vu.nl) writes:
> The drivers have to read and write the device registers in I/O space, and
> this cannot be done in user mode on the 286 and 386. If it were possible
> to do I/O in a protected way in user space, all the I/O tasks could have
> been user programs, like FS and MM.
On the 386, you could run the drivers in V86 mode, which sort of counts
as user mode and allows access to I/O registers if the kernel sets things
up to allow this.
Tim Smith