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So it seems to aim for the same niche as Lua/LuaJIT.

Game scripting - check, basically _the_ game scripting language
Simple interfaces, small runtime - check, ~500kb for all of LuaJIT on x64.
Numeric computing - check, LuaJIT does very good job optimizing numerics. Also check GSL Shell - LuaJIT + some extensions + bindings to GNU Scientific Library.
For servers - no concurrency, but being extremely lightweight does a good job on servers as multiple processes.
DSL and glue language - check, metatables and userdata really help there. Look at LPeg, for example
Simple C interfaces and automatic binding - LuaJIT's FFI does a pretty good job. While not automatic, copy-pasting from preprocessed C headers is usually all you need.

Plain Lua is nice and all but LuaJIT is where the fun is. It blows the doors off of any other scripting language (and many compiled languages) in terms of performance. I actually have some LuaJIT financial data processing code that runs faster than anything I have been able to code in C. It also has an incredibly awesome and fast FFI interface so you don't even need to write native code to interface with most native libraries.

Lua's Achilles Heal is string performance. It does have awesome tools like LPeg and has powerful string handling functions but if you're handling massive amounts of string data then it starts to bog down because of the string interning. It's still very fast and usually faster than other scripting languages like Python (not as fast as Perl though) but it is a long standing problem that pisses me off considering how fast it is otherwise.

I actually remembered one other UI toolkit that, while little known, is also very frugal. Like wxWidgets, it also wraps native widgets, though it seems to do a far better job at it (see below - I figured I'd check it out as well). It also has a distinction of being the only portable ANSI C toolkit wrapping native widgets that I know of.

The toolkit in question is IUP. Note that, even though they talk about Lua a lot, and it is designed to be used rather conveniently in conjunction with Lua, the library itself is pure C.

Now for the test, I took their precompiled libraries (which, by the way, means no LTCG, and I'm pretty sure it's optimize-for-speed rather than optimize-for-size), and their MDI sample. That one is actually more featureful than the one I used from wx, because it also showcases some of their widgets in MDI child windows (screenshot). And yet, the binary is a mere 360Kb - now we're talking!

Too bad they only wrap Win32, Gtk+ and Motif, and not Cocoa.

My understanding is that lib(dvd)css2 is in a legal limbo -- despite a quick search on Google, I can't find a single citation to show that it is expressly forbidden. However, there are warnings about using it and similar technologies all over the net.

So what? If "they" (whoever "they" may be) don't know you are using it, who cares? Well, for instance, what happens when you carry your laptop on an international flight, and as you return to the country, Customs asks to search your laptop?

I might just be paranoid, but it's something to keep in mind.

True but Python is just the next step towards Lua which will eventually show everyone up. Lua is tiny, fast, easy to extend, and simple yet powerful enough to do anything the other scripting languages can do (the LPeg extension is especially excellent).

Although there is no real web framework for Lua, it's only because no one has taken the time (the Kepler project has done some work in this area but I don't really care for their stuff).

Parsing Expression Grammars are the future.

They are generally faster and more powerful. It's easy to do regular expression-like stuff as well as really complicated things like a programming language parser.

Lua's LPeg extension is really excellent.

Here are a few more links:
http://userful.com/
http://cambuca.ldhs.cetuc.puc-rio.br/multiuser/
http://linuxdevices.com/news/NS4818008579.html

It's a bit dated, and the patches to the X server sources will almost certainly have to be adjusted to work on the current sourcebase, but here's a HOWTO from someone who did it.

It's the third hit on a Google search for "multiple keyboards X11", BTW.

Influence of Scheme on Lua design is well documented by the authors themselves. As for ECMAScript, it's really fairly obvious to anyone who has seen both Lua and ECMAScript, that their basic building blocks (Lua tables and ECMAScript extensible objects) are very similar.

"...so how am I to enjoy this feat of modern technology from a LINUX desktop."

Mmm, nothing like the smell of proprietary codecs on the open web. You can do it. One approach is to get xine from here and add the w32codec-0.52-1.i386.rpm. And get the MediaPlayerConnectivity plugin for Firefox and you should be able to view it.

xine rpms from cvs

It's a bit convoluted, but here's how to play these videos on Linux without having to delve into HTML and JS, and without having to use an embedded video plugin (lots of which seem to lock up and crash frequently):

- Install the GreaseMonkey extension to Firefox: http://greasemonkey.mozdev.org/
- Install the Unembed script for GreaseMonkey: http://dunck.us/collab/GreaseMonkeyUserScripts
- Install xine and the Windows codecs: http://cambuca.ldhs.cetuc.puc-rio.br/xine/
- Go to http://www.cnn.com/video/player/player.html in Firefox (the links on each story don't work, they check to see if WMP9 is installed, and then they fail)
- Click on the story you want.
- Right-click on the title above the embedded video (it's the name of the video in blue text, and it's in the same frame as the embedded video). Select "This Frame->Show only this frame" from the context menu.
- There should now be a link next to the video that says "[download]".
- Shift-click on the "[download]" link to open it in a new tab (right-click doesn't work, so you can't copy the link destination).
- Switch to the new tab, and press Ctrl-L Ctrl-C to copy the URL.
- Open a terminal, and type "xine " then Ctrl-Shift-V to paste the URL. Press enter and the movie should play!

Phew!

Granted, I assume that this is informative and accurate, but for God's sake, its 2005. Aside from Microsoft's DRM junk in WMV9 formats, is it still that difficult to view a movie from the web?

The first time I viewed an MPEG that I got off the internet was something like 1994, and the directions were something like 1) download MPEG from FTP site and 2) start whatever Sun called their media player at the time and open the file in it.

It's a bit convoluted, but here's how to play these videos on Linux without having to delve into HTML and JS, and without having to use an embedded video plugin (lots of which seem to lock up and crash frequently):

- Install the GreaseMonkey extension to Firefox: http://greasemonkey.mozdev.org/
- Install the Unembed script for GreaseMonkey: http://dunck.us/collab/GreaseMonkeyUserScripts
- Install xine and the Windows codecs: http://cambuca.ldhs.cetuc.puc-rio.br/xine/
- Go to http://www.cnn.com/video/player/player.html in Firefox (the links on each story don't work, they check to see if WMP9 is installed, and then they fail)
- Click on the story you want.
- Right-click on the title above the embedded video (it's the name of the video in blue text, and it's in the same frame as the embedded video). Select "This Frame->Show only this frame" from the context menu.
- There should now be a link next to the video that says "[download]".
- Shift-click on the "[download]" link to open it in a new tab (right-click doesn't work, so you can't copy the link destination).
- Switch to the new tab, and press Ctrl-L Ctrl-C to copy the URL.
- Open a terminal, and type "xine " then Ctrl-Shift-V to paste the URL. Press enter and the movie should play!

Phew!

Have you tried these RPMs? http://cambuca.ldhs.cetuc.puc-rio.br/xine/

These RPMs worked for me hassle-free. And it is better than a commercial version in one respect. When you click next chapter or fast forward, it does it! Commercial DVD players have to honor the block forwarding encoded in the DVD.

then someone applied the patches for you.

one method

a second method

In short, see http://cambuca.ldhs.cetuc.puc-rio.br/multiuser/for the XFree86 patches.

I have this working (and working quite well) with the following hardware configuration:

Asus A7V600 in an Antec Sonata case
AMD Barton 2500+, 1GB RAM
3 40GB ATA disks

First user:
Matrox AGP G450 dual, with two heads, using Xinerama, PS/2 keyboard and rodent

Second user:
ATI Radeon 7000 PCI, one head, and with a USB keyboard and rodent

(OS is Fedora Core 1, with a patched X server)

It's fast, stable, quiet (the Sonata is a really nice case), and environmentally friendly (half the power, solid waste, etc. of having two PCs)

The only real issue is that switching sound between the two 'sides' is currently manual (either plug/unplug speakers, or a switchbox, or a splitter)

In Windows, there are only two modes: clone screen and make all the screens a single desktop. XFree86 (which, I'll consider for the point of argumentation a part of Linux) has much better support, and you can even make many seperate, independent desktops, one on each monitor(very useful for monitors that are of different sizes).

Though seemingly useless unless your budget is really tight, you can even hook up an extra USB keyboard and mouse, and have two people simultaniously use the same computer locally. More info here.

The number of things you can do with XFree86 and Linux is endless, and features are developing very fast. Haven't looked at Linux lately? Look again.

everything on this page (if you're a redhat person).
here
Works beautifully on nearly everything I throw at it. Although the mozilla plugin crashes a lot. Might have to try out the mplayer kind that someone else has posted.

via RedHat 9 and the multiple XFree86 hack

How does that work? This approach? Or is there a better way to attach individual USB keyboards to separate X servers?

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.

Um, even if support is JUST about there, it's not there. Remember - you are dealing with a closed source system. Kinda like being in a jail cell with the keys hanging on the wall outside that you can barely feel with your finger tips. They might as well be on the far side of the room though.

With open source, you have the power to do whatever you need to do. See this project on multi-user X for an example. It's not pretty, but someone got it to work.

The original poster was quite correct. MS will Never support this for a couple reasons that I can think of off the top of my head. First, there just isn't enough demand to pay for the development. Second, they make more money off selling multiple copies of software.

Frankly, I agree with the other comments though - the work to do this just isn't worth it. You can get a second-hand fairly decent system on ebay for a hundred bucks, or a Brand New linux system from Walmart for $200. It just ain't worth messing with.

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.

http://cambuca.ldhs.cetuc.puc-rio.br/xine/w32codec -0.52-1.i386.rpm

Here in Rio de Janeiro, Brazil, the universisty I went to set up a similar program, named Instituto Genesis (Genesis Institute). You can check their web site in portuguese for more info.

The success rate is high, with graduate companies making good profit. A coincidence (or not) I work at one of those companies, and we are doing very well. The initial support given by the program was a very nice push.

I am on the wrong side of the country. However I will tell you what worked for me.

I started with Xine. They have various useful links. I needed the regionset utility, which you seem to have an alternate solution to. :-) From there I went to this foreign-hosted site from which you can get Xine in various forms. I had the best luck when I compiled everything from source. There are dependencies, so I had to compile in order. I forget which order, but I didn't have much trouble figuring it out, and you shouldn't either.

I will also send you a private email so that you can ask me any questions that come up. Its title will be "Followup to /. post" and the domain will be operamail.com.

The Xine video player has a feature set similar to MPlayer, but also comes with courteous developers and a ton of RPMs for easy installation on a variety of Linux distros. DEBs too.

...when someone begins to develop a truly original interface, instead of immitating Windows. Don't get me wrong -- Gnome and KDE are monumental achievements, and I congratulate their programmers. But what about all the really new and interesting ideas out there? Isn't creativity and exploration a goal of "free" software?

How about:

• Berkeley's Group for User Interface Research
• Semiotic Approaches to User Interface Design
• Xerox PARC, User Interface Research Group

While chasing Microsoft, let's not forget to stop and smell the alternative roses...

You know, I never read the article that is cited here. I did some research on my own about 2 months ago, when I was looking for a video player for my new Linux boxes. And I came to a conclusion that appears to be roughly similar to what people are saying about this article: in short, the MPlayer developers are rude, condescending, and foul-mouthed. I think that is their right. They made it, they can do/say whatever they want about it. But I also think it is legitimate for people to then say "I don't want to associate with these people." And why should you have to, when there is an excellent alternative that also plays Quicktime video (sans Sorenson), and comes in RPM format for SuSE, Red Hat, and Mandrake. So you can get an equally-good player, with more courteous developers to back it up, and with no need to compile unless you enjoy that sort of thing. This is market competition at work, and it appears to me that Xine may be a winning alternative.

Tiling windows seems like a far more intuitive way to manage windows on a PDA. Overlapping windows is absurd on a PDA, IMO- there's simply not enough screen space, even on an iPAQ (which still has a lot less than on a Newton MP 2x00). Having a full-screen setup like Palm apps doesn't quite work either, as it restricts you to a single task at a time.

A guy in your exact situation solved that problem very nicely:

http://cambuca.ldhs.cetuc.puc-rio.br/multiuser/

No X terminal required.

Actually, there is one:
RedHat 7.x + ReiserFS

But don't use resierfs for /boot, as the version of lilo shipped with RH7.1 is unable to read reiser.

Here's something I would like to see: an interpreter for C code that follows exactly what gcc would do. Then you could make a nice GUI environment for programming, where everything happens as you type it with no compile cycle. Then at the end you compile everything to get speed.

I use reiserfs on many of my machines, but agree that Reiserfs is not quite ready for mission critical work. I know what I am doing, and I accept the risk of using reiserfs. However, it is a pain in the neck for me to install Redhat on ext2, recompile the kernel then copy the root partition every time I create a server. I will also probably use Mandrake 8.0 as a rescue disk because Redhat 7.1 wont have reiserfs support.

Would it be too much to ask for an Official but EXPERIMENTAL-DO-NOT-USE-UNLESS-YOU-KNOW-WHAT-YOU-A RE-DOING Redhat 7.1 Reiserfs capable installer? I love Redhat for my servers, but I and many others would hate to to rely on a 3rd party Redhat ISO sets downloads from some guy in Brazil for an easy installation.

Would it be possible to release boot.img's that are Reiserfs capable, or would such a beast need entire ISO's?

If Redhat is worried about supporting these unsupported users, perhaps you could hide it in expert mode, and have disclaimers saying, "REDHAT DOES NOT SUPPORT THIS. USE AT YOUR OWN RISK."

I picked up Lua after reading this article about it in Dr. Dobb's Journal for use in Grim Fandango. (It has since advanced and yet simplified in tremendous ways... The article is about version 2.5, and it's now at version 4.0.) In addition to being a beautifully simple yet expressive language, Lua also has one of the cleanest codebases I've had the fortune to hack around in. The compiler/interpreter are all easily navigable... Comments are sparse, but well-placed and thoughtful; there need not be more because most of the code clearly explains itself. It's all written in straight ANSI C, and is instantly portable to just about everywhere without even any configuration macros. It's extensible in clean, logical ways... and oh yeah, it's BLAZINGLY FAST.

I picked up Lua after reading this article about it in Dr. Dobb's Journal for use in Grim Fandango. (It has since advanced and yet simplified in tremendous ways... The article is about version 2.5, and it's now at version 4.0.) In addition to being a beautifully simple yet expressive language, Lua also has one of the cleanest codebases I've had the fortune to hack around in. The compiler/interpreter are all easily navigable... Comments are sparse, but well-placed and thoughtful; there need not be more because most of the code clearly explains itself. It's all written in straight ANSI C, and is instantly portable to just about everywhere without even any configuration macros. It's extensible in clean, logical ways... and oh yeah, it's BLAZINGLY FAST.

Interesting links on Self can be found here.

Where Pliant syntax is discussed, it is said that it is original because "The Pliant parser is original in that it doesn't rely on an automaton derived from a grammar. It is simpler, but more customizable and therefore much more powerful. "

I'd like to point out that the parsing extensibility of Pliant can be found in the Forth language and I believe that Rebol may also have some of these advantages. The language Lua also comes to mind as a language with syntactic extensibility.

---

Javascript turns out to be really suitable. It's easy to pare down, has a good native interface, can compile to bytecode at runtime, and supports multiple contexts.

BTW, also worth a look are tinyscheme (which is a nice small embeddable Scheme), Python, Lua, and the fairly obscure ICI. ICI is a very nifty C dialect for scripting but it doesn't seem to be intended for embedded applications.

Nothing wrong with rolling your own, though. Especially if you've got a lot of scripters to support. I'm interested in seeing how Q3A's plans for scripting in ANSI C (using lcc) turns out.