From: thoth@uiuc.edu (Ben Cox) Subject: Re: inb/outb babble.. was Re: Problem with inb and outb.. Date: Sun, 14 Jun 1992 23:00:07 GMT
techs@pioneer.unm.edu (Erik Fichtner) writes:
>for it, but for a lot of things, like a simple inb from the video display
>asking what mode the display is in should be allowed.
There is no such thing as a "simple inb from the video display asking
what mode the display is in".
Numbered video modes are a fiction perpetuated by BIOS firmware; if
you aren't using the BIOS, those numbers have no meaning.
>My friends's goal is to hack the kernel to allow switching between graphics
>consoles so that he can run X on one console and GeoWorks under the dos
>emulator. ;-) It'll be a cool hack if it works. so will the port stuff,
>i think.
It will be more than a "cool hack"...
>Ugh. This is a good idea for devices you KNOW about. like the keyboard,
>video, serial, parallel, and so forth. but what if the DOS emulator
>wants to talk to... a Colorado Tape Drive, for instance. That's not
>something that Linux even understands.... nor do I, or I'd write a kernel
>patch... Since it's not being used, i see no fault in letting something
>that understands it deal with it unrestricted.
For ports that Linux doesn't know about, there is no reason not to let
a process use those ports directly.
You only need to emulate ports that you need to keep the user from
scrozzling.