Multiple Users and Multiple Inputs on One Machine?

BozoForPresident asks: "Not long after seeing a dual monitor setup for the first time I thought how useful it'd be to plug in another keyboard and mouse for a second user. That $4000 dual headed laptop (reported on Slashdot on Sunday March 16) becomes a more viable purchase when you add a couple of USB keyboards and mice for an additional user. Microsoft will never do it but how difficult would it be to make Linux handle 2 (or more) streams of input and direct them to their respective windows?"

Comments

Congratulations

[__past__]

You have just invented the serial terminal. Maybe you should apply for a patent.

Re:Congratulations

[tenman]

You haven't been marked at troll yet, so I'll tell you why this is a great ask slashdot post. It boils down to the fact that not everyone knows as much as you, or about what Linux can do for them. It would seem to me that if you could answer this poor guy's question, instead of trying to make yourself sound powerful and mighty, the world just might be a little better place to live. If you don't think what I'm saying is true, then check out the little culture of open Source Developers. And if you don't believe in the Open Source philosophy, then why are you wasting your time with Linux anyway? Why don't you just use some other UNIX? Please stop the high and mighty crap. No body cares that you have more geek'sperince, and the people who might care, can't because your to busy trying to tell them how stupid they are. There was a point in time that you didn't know about serial terminals. There was a point in time where you got introduced to the concept.

Have a nice day.

The Recipe

[zapatero]

For second serving:

Add video card. Sift in mouse port and keyboard device (USB recommended when serving more than one). Let blend in x11 conf file. Bind X11. Serve.

Don't forget audio. Can be nice to have multiple
audio out as well.

Hilarity ensues as multiple X desktops compete for such things as CD Drives.

It shouldn't be hard at all.

[PurpleFloyd]

Just get a USB hub, a second video card, a USB keyboard, and a USB mouse. Then run two X sessions, each configured to use one K/V/M configuration. The only issue is if you want to run high-end 3D graphics on both monitors, since you can only fit one AGP card into a PC. You might be able to get around this with one of the Matrox or ATI dual-head boards, but I don't know that for certain.

Incidentally, you may want to check out this review of a product that does something similar in Windows, again using multiple video cards.

Alternately, you may want to cruise Ebay for some secondhand X terminals. While they tend to be ridiculously expensive new (on the order of a whole new PC), you may be able to find someone with a few they just want to get rid of. Of course, check out the specs before hand and cruise Google to make sure that they'll work under Linux without any special hardware or software. X may be an open protocol, but it never hurts to be sure.

Re:It shouldn't be hard at all.

[grotgrot]

ThinSoft also have a product that does it for Windows.

Re:It shouldn't be hard at all.

[glitchvern]

Actually it's harder than this, due to problems in linux with the virtual terminal locking code. You end up having to compile a completely seperate X server with all the virtual terminal code removed. Details here. These guys are working on fixing linux's virtual terminal problems. I think the new virtual terminal code is one of the things not making it into 2.5 which will be put into 2.6 at some later point.

Difficult? You jest, sir!

[Pogue Mahone]

It's what X is designed to do, right out of the box - provided that your graphics card (and its driver) can configure the 2nd output as a separate display (nvidia can). Just read your XF86Config file one day and see! The only "problem" you might have is allocating the sound channel(s).

BTW did you know that you can also run multiple virtual X sessions (similar to the virtual terminals but graphical) on the same display/keyboard/mouse? I have 2 sessions running on my machine at home.

With USB devices and a recent XFree86, no

[leonbrooks]

The sticky problems are still with the Linux Console code, in that it doesn't really believe in more than one console with keyboard. However, USB keyboards are easier than PS/2 keyboards (easier to not route through the console), and mice are a non-issue (again, do not route through GPM).

As an alt to an X terminal, try a diskless fanless thin-client box. Motium make those with some really special features, but I don't know if the whizz-bang ones are ready for sale yet.

Re:With USB devices and a recent XFree86, no

[PurpleFloyd]

How would you hang more than one PS/2 keyboard off one machine anyway? I don't think I've ever seen any system that could do that, which is why I recommended USB (although serial mice would work just as well, now that I think about it).

Also, it seems to me that you wouldn't really need more than one textmode console, since you can run xterm/rxvt/konsole/gnome-terminal on an X-only KVM head. The only times you really need a real console are during bootup and emergencies, when two people using the system simultaneously wouldn't be a real asset.

There is software for windows to do up to 5

[stienman]

A company called thinsoft has a product called BeTwin which does exactly what you're asking.

Hook up to four additional USB keyboards and mice, and a monitor for each station (obviously you'd need more video cards if you want more than two stations) and it treats them all as seperate computers.

I found out about it because MSI bundles a two station version with the geforce 4x00 cards. I haven't tried it, though.

It works for windows.

-Adam

Re:and then ?

[Anonymous Coward]

no and then!!!

Re:and then ?

[Pathwalker]

Could someone please clarify why 2 people on one bastard PC would be better than 2 people on two normal PC's with some Cat-5 between them

Software Licensing - or at least that's why I was asked to look into some bizarre korean multihead cards back in 1999.

At the place I was working at that time, they used some expensive software that was licensed per processor. If one user used the software on a dual cpu machine, 2 licenses would be checked out. If he was on a single CPU machine one license would be checked out. Multiple instances of the software running on the same machine did not check out any additional licenses.

The idea was, to stick some of these strange cards into a bunch of machines, and put the users who were in training on these boxes. The resule: 2 users per license, saving up some licenses for the people who needed to run the program on the multicpu boxes.

The cards were completey unsuitable, and burned out quickly, so the project never went anywhere.

Prior Ask /. on the same topic

[Andrew Lockhart]

This question was asked quite awhile ago here.
There was a tutorial mentioned in the comments.

Re:Might as well have a PC for each person

[aminorex]

Whereas:
Keyboard $10
Mouse $5
Cheap dual-head AGP video $65
Linux: Free
The look on Bill's face: Priceless.

Was on LKML recently

[ggeens]

This question was asked on the Linux kernel mailing list a while ago. The response was (from memory):

Yes, you can have 2 keyboards, mice and video cards in a single PC. And you can run 2 instances of X on different virtual consoles. But, there can be only one active VC at any time, and it's hard to change that limit.

The conclusion was that it would probably be easier and cheaper to set up an X terminal.

you can do it on windows already

[aderusha]

sorry to shoot down the trollish anti-ms nature of this post, but this has been available on microsoft platforms as far back as NT 3.51. the first terminal server/citrix platform utilized this technology (multi video/key/mouse, not terminal sessions over ipx/ip). it's now called "ultra thin client" technology.

check here, here, or here.

Re:Might as well have a PC for each person

[mpechner]

I wrote my response to doing this in a business environment. Second OEM for the same machine. Illegal, welcome to club fed. Your a felon. Can you spell Butt Buddy. As for using linux, I try once a year. I take a linux machine and use it. OpenOffice - Give it another 2-3 years. Visio replacements - not bad for normal flow charting. Falls apart for UML. Outlook - The Ximian Evolution connector is a peice of junk. Even small companies use Exchange. POP does not do meetings. Project managment: Mr Manager falls apart once you get multiple levels. Accounting: even the small company using QuickBooks can't use GnuCash. WINE - still too buggy. VMWare - my work around. But this is for one person. You still need the Full legal retail copy per person of all your software. Believe me, I try. In the real world of most companies, you need office, you need windows. A big rule of IT, search for the software that does what you need, then buy the computer for it. Unfortunately, this means windows. If there was a meeting manager that tied in with an LDAP address DB, and worked under linux and windows, I'd do a happy dance. I'd have a real solution to purge the world of exchange.

Already done

[Yenya]

I use this setup for ~1 year now - two VGA cards (one AGP, one PCI), two keyboards (PS2 and USB), two mice (PS2 and USB). You need to patch the XFree86 server. More info here.

Re:I saw this on windows back in 1999

[Holi]

The product you are taking about is "Buddy B-210 Virtual PC" Here is a link to a review of the product. http://www.overclockers.com.au/techstuff/r_buddy_b 210/ And I hope you saw english as it was developed by an Australian company. Whether is is still made I cannot say but you may be able to find it on ebay.