Re: Planning The upgrade

[Aivils <ai...@un...>]

On Saturday 14 August 2004 19:08, jam...@em... wrote:
> I have lookd with interst at the many "how to pages" for setting up a dual 
> headed system,a nd it seems tha tmost of them were last updated when Kernel 2.4 
> and XFree86 were still the standard.
> Currently I am using 2.6 with the ALSA patches, and X.org as my Xserver. and 
> Would like to be able to upgrade my system while downgrading as little software 
> as possible.
> The most promising tutorial I have found at 
> 
> http://cambuca.ldhs.cetuc.puc-rio.br/multiuser/
> 
> include the following section.
> -Proper kernel 2.6 support
> -Aivils Stoss notified me that multiple keyboards are possible without any kind 
> of 2.6 kernel patching (see above). The trick is to request exclusive access to 
> the event device, so that keyboard handler would not receive any event. This 
> requires only small changes to the XFree86 patch (actually x.org fork as i 
> expect the old XFree86 to die silently with their new license...). Aivils 
> explains:
> 
> data[0]=1;
> if (ioctl(fd, EVIOCGRAB, data) == 0)
> printf("exclusive access granted");
> 
> "where fd is file descriptor of /dev/input/eventXX. I dont know wherethat is 
> documented.
> 
> If You will highly polish Your solution, then take a look into Debian testing 
> distro: Debian testing xf86 already includes 2.6.XX event device support.
> 
> Please check out this patch against xf86 4.3.0: 
> http://ftp.debian.org/debian/pool/main/x/xfree86/xfree86_4.3.0-7.diff.gz (grep 
> evdev). You can find this link via www.debian.org. Unfortunately i do not know 
> how to works Debian. I know only some linux-ruby testersuse this event 
> interface. xf86 event interface means usage of /dev/input/eventXX instead 
> standard /dev/ttyXX for keyboard and /dev/input/mouseXX for mouse.If You will 
> run multiple local Debian xf86 You should applay manualy Your own "TTY 
> dependency remove" patch and seems add EVIOCGRAB to disable 2nd, 3rd ... 
> keyboard presence on TTY and "xf86 PCI interference remove" patch.
> 
> Advantage: kernel remain unpatched. You can use two PS/2 keyboards under 
> 2.6.XX." 
> 
> With All of the talk of Ruby kernel patches, this almost seems too good to be 
> true...and I don't really understand where to place those lines in the patch 
> either(I am learning linux as quickly as oppurtunity permits).

I mistake little when i send mail to Miguel. Those lines already are included
in the Debian evdev patches.
* X server will use mouse and keyboard - for this You need Debian evdev
pathes. After applaying of pathes X server read mouse and keyboard events
from /dev/input/eventXX.
* X server must not stop any video adapter in system - for this need Debian
isolateDevice patch.
* X server must not open /dev/ttyXX - take a look into Miguel' s patches

If You are capable create this 3 things, then You can use "multiuser"
system with vanilla kernel (2.4 or 2.6).
It is not so hard. Seems Miguel are tired.

You are your own!

Most users of this mailing list use patched linux kernel, i hope :)

> I haven't begun yet on seting up my system, or even purchasing additional 
> components until I get my homework done on the software.
> It would also seem, with two monitors windows could easily be setup as a 
> xinerama system.  X.org is easily configured likewise (it is part most of the 
> installation tutorials I have read).  How simple can the switch be made 
> from "xinerama" to "dual-head" mode? 

Some end-users are not capable install fresh kernel from source.
Check yourself :)

> Has Hot switching (commendering the other  
> monitor while others are logged off, and being able to relinquish it to allow 
> others to log on) been explored yet?

?
Root can only kill/restart aditionals X servers. i do not know how to command
or run some programm on another X server.

Aivils

P.S. Also exsits nested X server Xnest. May be anyone will patch it and so
run nested X with separate, unnested keyboard/mouse ?