Re: [Linuxconsole-dev] writeup

[Jim P. <ji...@ag...>]

James Simmons wrote:
> A console can be many things. It can be also a serial console like a real
> vt100 plugged into your serial port. It can also be a virtual device built
> from a keyboard and a video display. A head is a bit more flexiable. It's
> a collect of input and output devices. A head is equal to a active VT
> normally. If you ave more than one head than you have more than one
> active VT. What I like to see is a raw interface to hardware devices
> (/dev/fb,/dev/input, /dev/dsp) such a a userland app can grab them to
> expand what a head is. This keeps the VT code simple and yet allows a
> userland app great power. Of course you have to manage things so people
> don't grab things that already belong to someone else.

If I suggest a concrete example, can you tell me which are heads and which
are consoles ?  This is hypothetical example, that I think may be possible,
if I understand correctly what is being suggested.

Let's say we have two desks back-to-back, a machine on the floor, with two
video cards, and two monitors, two keyboards, two mice plugged in.  Two
people use that one machine, independently, running console-programs on
several screens (switched with Alt-Fn), and also running X-Windows and
X-Windows apps.  Physically we have two independent `stations' (by which I'm
meaning seat-desk-keyboard-monitor).  Are these two `heads' ?  Or are they
two `consoles', with multiple `heads' being switched between with (Ctrl-)
Alt-F?.

Let's say we add a VT100 terminal on the next desk on a serial cable.  Is
this another `console', or `head', or both ?  Or is just one of these three
`stations' really considered to be the official `console' of the system ?

Things seem to get much more confusing if we think of someone with one
keyboard/mouse and two monitors, with some hot-keys to switch the stream of
input events between one monitor or the other (between the applications
visibly running on those monitors).  But this could be seen as a kind of
emulation of the two `stations' above - somehow an emulation of two
keyboards/mice through just one.

Or is this too inflexible a viewpoint ?  You may want your two monitors to
work in cooperation, perhaps moving apps from one monitor to the other, or
even having X-Windows spanning two monitors.  To me this bunch of hardware
counts as one `station', but does it count as multiple `heads' or multiple
`consoles' as well ?  Confusing.

Any thoughts ?

Jim

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