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The Virtual Private Nightmare: VPN

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Maybe the 'P' really stands for Public...
Here's a question: What's the number 1 vector for security outbreaks today? Given the title of the article we hope you answered Virtual Private Networks (VPNs). Today's convenient world of mobile access to critical applications and information has come with a hefty burden for the world's already overburdened security teams.
(and here are some nightmare prints) read more...
mail this link | permapage | score:9126 | -Ray, August 4, 2004 (Updated: April 24, 2012)

Linux hardware review: Biostar iDEQ 200V Cube

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I ordered my Biostar iDEQ 200V from Newegg a couple of weeks ago. My goal was to build a small form factor Linux system that was quiet, fast, inexpensive, reasonably flexible, and easy to work on. I also wanted a Socket A motherboard so that that I could take advantage of AMD's excellent and cheap XP 2500+ Barton core processor. I already had a Maxtor 40 GB disk drive, a Sony CD-RW drive, and a floppy drive so off to Newegg's website I went, credit card in hand.

I ordered the Biostar iDEQ 200V ($189), a Crucial 512 MB DDR PC-2700 DIMM ($79), and an AMD XP 2500+ (Barton) ($91) processor. [Note that some of these prices may have changed since I last checked them.]

Even though I saved a little more money by selecting the 'Free FedEx Saver Shipping' option, my order arrived in three days. I unpacked the Biostar system first. It is housed in a 210mm wide, 187mm tall, and 323mm deep aluminum case [8.3 inches wide by 7.4 inches tall by 12.7 inches deep]. Four thumbscrews on the back lets you remove either side panel and the top panel without tools. Inside the case is a red system board with an 8x AGP slot, a single full-size PCI slot, two 184 pin DDR slots for up to 2 GB of PC-2700 memory.

Already installed are all the cables you need for an IDE system, prerouted, labeled and cut to exact length. The cables snake around the chassis so cleanly that they are barely visible. The cables are labeled in easy-to-read lettering on sturdy pull-tabs. This is a very well-organized and uncluttered system.

A custom heatsink fan assembly is included, already attached inside the system. This makes the already easy task of figuring out how to mount the CPU cooler almost trivial. Once you've removed the heatsink to install the CPU, you already know how to reinstall it. While you don't really need the included manual to assemble this system, you'll probably want to scan it first just to make sure you install the parts in the recommended order. If you follow the Biostar manual, you won't wind up with one part blocking access to another.

Also included in the iDEQ shipping carton was a pair of brackets to cover the optical and floppy drive bays in the event that you don't install drives in those bays. There was also a set of cables for a serial ATA (SATA) drive. Since I'm not yet the owner of a serial ATA drive, I didn't test that feature. However, Linux kernel 2.6 will support the SATA controller included on the system board and I understand that it already works with the current 2.6 test kernel. [Update 3/7/2004: Here and here are comments based on attempts to get SATA working on 2.6 with no success. It appears that our original information was incorrect and RAID is not yet supported on this system with Linux 2.6. -Ed.]

The system comes with a 200 watt power supply, plenty for the XP 2500+, the three drives, and the AGP and PCI slots -- as long as the more power-hungry video cards are avoided.

The AMD XP 2500+ came with a large aluminum heatsink/fan with a thick copper plate on the bottom. I set it aside to use with another system and, after removing the custom Biostar cooler, plugged the CPU into the socket. The heatsink easily and firmly latches down with a pair of springy levers.

I put the Crucial 512 MB DDR333 DIMM in one of the two memory slots, then turned my attention to the drives.

The hard drive bracket slides out of its slot when you press the trigger release making it a snap to install the Maxtor disk. The floppy bay is centered beneath the 5.25" optical drive bay. I put a floppy there and then installed the Sony CD-RW drive, carefully routing the audio cable alongside the IDE cable so as not to compromise the clean look of the system's interior.

I've assembled about 25 systems and this was the easiest build so far. Everything is where it should be, there is enough room to easily install the components, and everything fits just so. I hooked up the system and popped in a Red Hat 8 installation CD. Using a distribution several months old revealed one problem -- in addition to the aforementioned issue of SATA support. The sound chip wasn't recognized. A little research showed that it, also, would be supported in Linux 2.6. Meanwhile, I bought a cheap but well-supported Creative Lab Sound Blaster 128 PCI ($24) sound card to solve the problem. After plugging the Sound Blaster into the PCI slot, I disabled the onboard audio chip on the mainboard and rerouted the CD-ROM drive audio cable to the Sound Blaster.

That produced acceptable sound without breaking the budget -- and should get me by until I can acquire and install a Linux 2.6-based distribution.

Other than that small sound support hitch, everything has worked perfectly under Linux. The iDEQ 200V is the quietest, fastest, and one of the smallest computers in the house. While it was intended to be a test machine for a while, it has quickly become my main desktop system.

Other features of this system include a sliding door that, when closed, covers the floppy and optical drive bays; a bright blue HDD activity LED; and two depressions on the bottom of the system that provides heat contact between the processor and chipset and the case. That last clever bit of engineering turns the bottom of the aluminum case into a compnent of the cooling system and helps keep the two hottest chips in the box running cool.

The Biostar's BIOS allows control of the processor bus in 1 MHz increments. Just as a test, I stepped up the speed until I had overclocked the CPU to 2 GHz from the XP 2500+'s base speed of 1.833 GHz. Since I'm more concerned that the system run cool inside my poorly ventilated desk, overclocking was not the ultimate goal -- so I reset the bus back to 166/333 once I was satisfied that 10% overclocking was within the capability of my components.

Overall, I'm very satisfied with the Biostar iDEQ 200V, the AMD XP-2500+, and the 512 MB Crucial DDR PC-2700 DIMM. The performance is excellent, it's a nice-looking system inside and out, and the price is certainly nothing to complain about.
System tested: Biostar iDEQ Barebone System for Socket A at 266/333MHz FSB AMD CPU, Model IDEQ200V

Specifications:
CPU Support: AMD Athlon XP (Socket A, Max.FSB 333)
Chipsets: VIA KM400 + VT8237
Memory: 2x 184pin (DDR333 up to 2GB)
IDE: 2x ATA133, 2x SATA(RAID)
Graphics: Integrated VIA UniChrome
Expansion Slot: 1x PCI, 1x AGP 8X
Audio: C-Media CMI9739A
LAN: 10/100 LAN
Extension Bay: 1x 3.5", 1x 5.25"
Front Panel Ports: 2x USB, 1x 1394, 1x SPDIF_Out, Audio ports
Back Panel Ports: 1x COM, 2x PS/2, 1x VGA, 1x RJ45, 2x USB, 1x 1394, 1x SPDIF_In, Audio ports
Power Supply: 200W(PFC)
Dimension: 210 x 323 x 187 mm

If you're looking for a small form factor computer that's a bit higher end, take a look at the Shuttle XPC SN25P Barebones, which supports the Socket 939 dual core chips.
mail this link | permapage | score:9116 | -Ray, December 9, 2003 (Updated: April 18, 2007)

Tutorial: Linux game programming with Ogre 3D

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This tutorial starts at the beginning with opening a window...
This tutorial series steps you through the process of creating a 3D shoot'em'up game using the popular and powerful Ogre 3D engine. The tutorials compile on both Windows and Linux.
read more...
permapage | score:9116 | -Ray, January 1, 2010

System monitoring: Icinga, Nagios, and Opsview

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Three open-source system monitoring software packages, two of which are derived from Nagios...
If in your work you are responsible for just one server, you will surely wonder: What is the best way to get the situation under control?

In the world there are good open source software that allow you to monitor the status of servers, services and programs.

In this article we’ll see an overview some of the softwares in this category, and in particular some related to Nagios...
read more...
mail this link | permapage | score:9098 | -Ray, March 24, 2011

Beginner Ubuntu Tips

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Twenty-five tips for Ubuntu beginners...
Adding another source for software is easy; once you've installed addrepo, you can do it in the terminal by typing something along the lines of addrepo deb http://mirror2.ubuntulinux.nl/ lucid-seveas all.

If you find new repositories online, they will usually give you the right details to enter. You could also do it graphically by going to 'System | Administration | Software Sources | Third Party Software | Add'. read more...
permapage | score:9086 | -Ray, November 9, 2010

Tutorial: Run multiple OSes with free VMWare Player

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This HOWTO will take you through the steps necessary to use VMWare Player to run multiple operating systems simultaneously on your PC.
VMware Workstation has always been (and still is) a commercial product, and you have to pay a fairly large sum to get your hands on it, but VMware have now released a free application dubbed “VMware Player”, which can run virtual machines produced by VMware and a few other companies. Yet, with some simple hacks, we can use VMware Player to run any x86 Operating System we like.
read more...
mail this link | permapage | score:9056 | -Ray, December 19, 2005

64-bit Desktop: SuSE vs. Fedora vs. Windows XP

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The 64-bit versions of SuSE and Fedora are compared against both the 64-bit version of Windows XP and the 32-bit versions as well.
To get a well-rounded breakdown of where Linux is going, and where it trumps (or fails against) Windows, we took the two largest 64-bit Linux distributions, their 32-bit counterparts, and the Windows XP 64-bit public beta for a test drive. The way that we are running the benchmark is slightly unique; we do not recompile or optimize benchmarks per hardware platform. Our goal is to see which out-of-the-box operating system performs the best with as much support as possible.
[If you don't already have a 64-bit box, here's a shortcut to building a 64-bit system based on an Athlon 64 dual core processor or a cheaper single core chip.] read more...
mail this link | permapage | score:9050 | -Ray, July 13, 2004 (Updated: October 28, 2005)

Benchmarks: NFS v3 vs. NFS v4 Performance

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NFS3 vs. NFS4 file operations speed compared...
NFS version 4, published in April 2003, introduced stateful client-server interaction and "file delegation," which allows a client to gain temporary exclusive access to a file on a server. NFSv4 brings security improvements such as RPCSEC_GSS, the ability to send multiple operations to the server at once, new file attributes, replication, client side caching, and improved file locking. Although there are a number of improvements in NFSv4 over previous versions, this article investigates just one of them -- performance.
read more...
mail this link | permapage | score:9044 | -Ray, June 20, 2008

Linux vs. Windows: Why Linux will win

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One of the oft-mentioned weaknesses of Linux, fragmentation, just happens to be one of its greatest strengths. A broad range of choices in an immature market is a good thing. Of course, choice does come at a cost. For example, there may be no standard way to do a particular task. Further, development resources will sometimes be split among two or more projects. However, these are weaknesses in the short term only.

One could similarly argue that evolution of species suffers from the same 'weakness' of fragmentation. However, in the long term, the survival and consolidation of the best traits results in an improved breed. Eventually, one of the many approaches to some desktop task will rise to dominance and show the market the right way to do it, and, at the same time, reduce the fragmentation problem.

Based on my observations, business continuity considerations are starting to place more emphasis on portable data formats and protocols. Relational databases, contrasted with the counter examples provided by Microsoft formats, are helping to raise awareness of the value of portable data.

For a private business to blithely entrust their data to proprietary formats and protocols is irresponsible at best. For a public company to do so can be looked upon as a breach of the shareholder's trust; an unnecessary liability. It's quietly overlooked now partly because of the ubiquity of the practice and partly because no Microsoft-dependent organization wants to point out a liability from which they also suffer. This situation will change with growing awareness of the problem and as the Linux-plus-free-applications option makes vendor lock-in increasingly harder to justify. The time is coming when the stock market will recognize and reward data independence among public companies.

Linux is entrenched in the server world. That provides a huge opportunity to expand into more and larger server niches. It also provides a small contributing stream of desktop users in influential places.

Major market shifts, when limited by ingrained attitudes, are generational. It takes the replacement of one generation by the next for a market to complete such a transition. Even after Linux comes to dominate in new installations, there will naturally be Windows holdouts for many years, in both homes and organizations. This diehard tenacity is not an unexpected sign of strength, but it will be interpreted as such by a certain class of industry analysts for many years.

The IT industry has an inertia that is almost unimaginable to someone who hasn't spent significant time immersed in it. Application systems built on one operating system or architecture are extremely expensive to port to an unrelated OS or architecture. While this effect does slow the uptake of Linux in business, it also prevents a sudden loss of the Linux market share. But, mostly, it masks the rise of Linux so that it is possible for much of the IT industry to simply ignore its growth. I think that this effect of the slow and gradual adoption of Linux is the main support for the ‘Windows has won the desktop’ analysts’ arguments.

Linux is free as in ‘free beer’. Yes, you can buy it -- and many do -- but when you pay money for Linux you are really buying something else: support, non-free components, and convenience, to name a few. The reality, however, is that Linux is as free as you need it to be.

Linux is also open. It can be extended, embedded, and used as needed without restrictive licenses and without fear of vendor lock-in. This characteristic of Linux can only improve Linux’s profile with each business continuity study and proprietary counter example. The significant restrictions of Linux’s license, the GNU General Public License (GPL), establish rules of redistribution, not limitations of use.

Linux is also scalable -- but just what does that mean? Scalability runs in several directions. To say an OS is scalable doesn't simply mean that it scales to very large systems. Rather, scale refers to the entire range from the very small to the very large. It refers not just to the vertical dimension but also to the horizontal, across arrays of clustered systems. On this measure, Linux truly excels. Linux powers an amazing range of systems, from tiny devices to supercomputers. Of the several operating systems that scale to very large systems, Linux seems to be the one destined to own the small end of the size spectrum.

Security may be even more important than scalability to the IT industry. Security concerns are also gaining mind share among home users as identity theft becomes more widespread. SELinux is beginning to be integrated into major Linux distributions -- which will expand the number of security-conscious IT shops that can deploy it. At the same time, Windows has spawned a healthy industry dedicated to screening out viruses and worms.

I believe that Microsoft's practice of neglecting security is one of the biggest reasons for Firefox's phenomenal success, just as it is steadily contributing to Linux’s growth.

Meanwhile, there are a few features that many Linux distributions are still missing out of the box. As each of those areas is addressed, end-user Linux adoption will increase. As this process adds to the size of the Linux installed base, the newly enlarged base will increase the value of solving other such problems, continuing to fuel the positive feedback loop. As Linux reaches ‘critical mass’, almost all of the other arguments against Linux will fall, one by one. For example, when major vendors start offering preconfigured Linux systems to home desktop users, one of the most persistent complaints against Linux, that ‘it is hard to install’, will become irrelevant. As many readers surely realize, Windows is difficult to install as well. The difference is that users generally don't have to install Windows. It comes preinstalled, and with a preconfigured 'restore' CD. The implication of this is that as Linux approaches critical mass, its period of fastest growth may still lie ahead!

Meanwhile, Microsoft's desktop network effect advantage is weakening due to cross platform software packages such as Firefox, OpenOffice, and, for programmers, gcc.

Even some game makers could conceivably abandon Windows by releasing custom Linux LiveCD versions of their games. Granted, there might need to be some embedded graphics support, but this need not be an insurmountable problem since many games only support a limited number of graphics adapters anyway.

Linux has a certain ‘coolness factor’ that appeals disproportionately to young people. Further, Linux is strongest among the technological elite, i.e., those who help and advise others, run websites, write code, and generally set technology trends. This slice of the market is more important to the future than their numbers suggest

Microsoft has, as they say in politics, ‘high negatives’. That is, a substantial percentage of people very much dislike Microsoft. These people will go to considerable efforts to avoid buying or using Microsoft products as alternative products become more visible.

Capitalism, like open source, is relentless and efficiency based. A central planner can never fully predict a market's evolution -- yet capitalism moves in lockstep with it. In much the same way, various Linux distributions will be born and die as desktop evolution relentlessly marches on. Even the current 'Linus' branch of the kernel can and will be replaced (forked) if it doesn't follow the main market closely enough. The ‘planned economy’ of Microsoft is at a disadvantage when facing the evolutionary dynamics of the laissez faire open source bazaar.

Compounding the problem for Microsoft, Linux is poised and ready to pounce upon any new, Windows-incompatible, hardware platform; perhaps IBM’s upcoming cell processor will be the next Linux success story. Linux runs on almost everything and gets quickly ported to new hardware. Linux is agile, Microsoft is not.

Microsoft's biggest remaining asset is probably the vendor lock-in ‘feature’ of Microsoft Office. Of course, that lock-in is also one of the biggest reasons not to use Microsoft Office. As free office suites achieve acceptable levels of command, feature, and file compatibility with MS Office, more and more user’s desktops will become available to Linux. Microsoft will, as always, try to leverage their current lock-in into future lock-in. But with the pace of office software development slowing as the market nears saturation, that is easier said than done. Changing Office to render a competitor incompatible will also hinder older versions of Office, creating more ill will. Also, if a competitor ever does achieve close compatibility with the current version of Office, customers will have the option of jumping to the competitor if Microsoft changes the file formats. With bad timing or a bit of bad luck, such a lock-in maneuver by Microsoft runs the risk of hastening the abandonment of Office.

Microsoft has always shrewdly leveraged their network effect and mind share advantage to maintain themselves and grow. They will continue to use this strength -- but they face many hazards. They must correctly identify the real threats early enough to fight and nullify them. Microsoft can win many battles and still lose the war. They simply can't win all the battles and yet their relentless adversary, Linux, can lose battles indefinitely and still come back to win the war. Unfortunately for Microsoft, ‘Linux’ doesn’t need to make a profit and can’t be put out of business by an upside down balance sheet.

Linux does, however, have one looming vulnerability. Microsoft could possibly kill Linux with some unwitting help from the Linux kernel team or the open source applications development community. Governments, through trademark, copyright, and patent law, wield such power over common business practices that runaway software patents -- like those now being issued in the US -- could kill off commercial Linux use and support in affected countries. For example, heavy participation in a scenario such as this one could lead to a near-death experience for Linux. This scenario, though, is best classified as a government action. Linux has already penetrated so many niches that the chances of Microsoft rooting it out via market mechanisms seem pretty slim.

And, no, Linux isn't yet ready for every desktop that Windows occupies. However, it wasn't long ago that Linux wasn't ready for many server roles either. The server situation has changed drastically just as the desktop situation is now changing. The desktop will change more slowly since it is not transparent to the user, but similar forces are pushing it inexorably forward. Each year new niches are added to the Linux desktop installed base and other, more established, niches grow. With each such increment of desktop growth, another marginal niche becomes viable. A few more years of this growth and the big market niches will gradually go from inaccessible to marginal to viable to dominated. No, Linux can’t yet replace Windows, but time is on Linux’s side.

Meanwhile, if you’re impatient, you can help to speed things up. Help a friend install Firefox or OpenOffice.org. Give a Windows user a Knoppix CD to play with or install a Desktop Linux distribution on their 'old' machine and show them a software repository full of nice, friendly, and free binary applications. If you’re a programmer, find an open source project that interests you and lend a hand.
mail this link | permapage | score:9042 | -Ray, May 8, 2005 (Updated: May 13, 2005)

Space Tyrant Index Page: Linux game server development project

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This page links to the various articles that have been published about Space Tyrant, a multithreaded, network socket programming Linux game server project in C.

Read below for the history and overview or just click these links for the articles:Space Tyrant is a C language Linux game server development project. It started out in February, 2005 as a humble echo server with high ambitions. On March 18, ST had its design and intentions announced to the world.
Today we kick off a new multithreaded, network socket programming project which we will call Space Tyrant. Our mission is to write an open source, multiplayer, networked, strategy game in the C programming language. The goal of this project is to make a solid code base which implements a simple space trading game upon which other games can then be built. The game will be a subset of The Last Resort (TLR) that currently runs at Ioresort.com. This project will be a learning exercise for me as well as for any interested readers. The current state of the source code will be released with each article update.
Source code to ST, then just an echo server, was not released.

Then, on March 27, 2005, ST was promoted to a crude chatserver.
This is the first code release of Space Tyrant. This is an early stage of development and, at this point, only implements the listening thread, the two IO threads for each player connection, and a skeletal game logic thread that does little beyond proof-of-concept code.
Next, on May 30, 2005, ST started to resemble some sort of incomplete text game.
It’s now possible to connect to the game via telnet and to create an account, log in, and be issued a ship. Once you’re logged in, there is a universe to explore filled with ports for buying and selling goods and planets for scooping free goods. From those trading activities you can earn money, called microbots. Other than trading to earn more money, you only use your microbots to buy fighters -- which you can use to attack other players or the neutral fighters that guard some sectors.
As of this release, the source code was placed under the GPL, version 2.

On June 26, 2005, Space Tyrant was released with many shiny new abilities. Players can now deploy fighters to guard sectors, navigate with the aid of an autopilot, rank the various players in the universe, and sleep peacefully knowing their alternate universe is being backed up constantly by a sporty new backup thread. Yes, good times are surely upon us.
If you’re looking for a planet, type the ‘L’ command that you would normally use to land on a planet in your sector. In the absence of a planet, the L key will engage the autopilot which will search for the nearest planet and give you a ‘/’ command to autowarp to it.
There is normally a copy of the development version of the server running on my decTOP on port 23. To access it, type (or click, if it works for you) the following command:

(telnet to my ST server)

The current development version of the code is usually at http://librenix.com/st/st.c but the individual articles link to the specific versions discussed in each article.

You can mail me about the project at spacetyrant [at] librenix.com -- or you can just telnet into Space Tyrant, as listed above, and send me a radio message. I'm likely to get that faster. ;)


The Space Tyrant project has a new website, SpaceTyrant.com, where the latest source code is always available. Also, new articles about ST programming and about ST gameplay will be posted there as they come available.


Information on The Last Resort follows. TLR is one of the two games that Space Tyrant is intended to replace someday. Space Tyrant has a long way to go before it replicates TLR's 25,000 lines of C code. So far, it has reused only about 40 lines of TLR code, a handy 'bit-plane' sort dating back to 1998.

  • TLR Survival Manual
  • Is this game for you? read more...
  • mail this link | permapage | score:9022 | -Ray, June 25, 2005 (Updated: April 26, 2011)

    Space Tyrant: A threaded game server project in C

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    [Update, June 25, 2005: A Space Tyrant home page has been created as a central index to the various ST articles, links, and files.]

    [Update, March 21, 2007: A Space Tyrant has its own website! It's small but growing and will provide quick access to the latest code and developments in the ST universe.]

    Space Tyrant: Today we kick off a new multithreaded, network socket programming project which we will call Space Tyrant. Our mission is to write an open source, multiplayer, networked, strategy game in the C programming language. The goal of this project is to make a solid code base which implements a simple space trading game upon which other games can then be built. The game will be a subset of The Last Resort (TLR) that currently runs at [offline]. This project will be a learning exercise for me as well as for any interested readers. The current state of the source code will be released with each article update.

    The game design: While my TLR game consists of over 25,000 lines of C source code and supports a web interface as well as telnet and a graphical client, this code will be far smaller and simpler. It will initially only support telnet and will implement a far simpler game design.

    Players will be able to telnet into the game, create an account, and play in a universe that contains ports, planets, as well as other players. Each player will be issued a starship, some cargo holds, and an amount of starship fuel. Additional fuel will be issued hourly and will accumulate in the starship. Fuel will be used to move the ship between sectors -- locations within the game universe -- and to dock with ports. Once a ship runs out of fuel it can't move at all until new fuel is issued.

    Players will be able to buy and sell commodities (Iron, alcohol, and hardware) between the three different kinds of ports. Each port type will sell one of the three commodities and buy the other two. Prices will be based on supply and demand with rarely-used ports offering the better prices.

    With the money players earn trading they will be able to buy more cargo holds to make their ships more efficient for trading. They will also be able to buy fighters -- small military drones -- that can be used to attack other ships or deployed to guard a sector and its contents. The fighters carried with a ship will guard it against attacks from other players.

    Games will run for a predetermined length of time, then reset and start anew.

    The programming model: Now, on to the software design. I've compared and considered various models for the server design. TLR is based on the forking model using inetd or xinetd to handle the listening and forking. While the forking model is inherently distributable to multiple processors, it introduces inefficiencies (forking multiple processes) and makes interprocess communications more difficult and slower.

    Next, I considered a non-blocking, single process model. In this approach, one process handles everything in a single thread. It would use non-blocking IO (read and write functions that never wait for completion but, rather, return immediately if they aren't ready to read or write actual data). The thttpd web server is an example of a non-blocking, single process server. It's extremely fast and efficient. However, this model is quite complicated to code, and, I believe would make it more likely to introduce subtle timing bugs.

    Next, I considered a pure multithreaded, single process model with a thread for each player. While appealing in many ways, this model would require the same kind of coordination between threads that the forking model requires between processes. Such interprocess communication would be simplified in that the various threads share memory, but the coordination issues otherwise remain the same.

    Last, I considered another multithreaded model, this time with only IO threads for each user and a single thread that implements all game logic. While that one central thread might someday be a bottleneck that limits scalability on large SMP systems, it does distribute the IO on any additional processors that might be present, and requires minimal coordination. In short, this model combines the logic simplicity of the non-blocking single process model with the coding simplicity of the threaded model, while separating the IO from the main logic. There will also be two other simple threads in this model. There will be a thread that listens for new connections and spawns the IO threads for each new connection. There will also be a thread that writes the data to disk periodically.

    This is the approach that I intend to take for this project. The code will be written for both Linux and Mac OS X.

    More info: I have set up an email address for programmers following this series to provide recommendations, bug reports, and other feedback. Send email about this project to spacetyrant [at] librenix.com.
    mail this link | permapage | score:9017 | -Ray, March 18, 2005 (Updated: July 26, 2008)

    Microsoft to push unlicensed users to Linux

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    Microsoft has long had a conflict of interest about software piracy. By pretending not to notice, they encouraged the use of unlicensed Microsoft software, thereby letting dependence on their formats, packages, and protocols grow. The time is approaching when that will change.

    Microsoft has historically made much noise and took little action against unlicensed users of its software. In the case of some developing countries, the reason was obvious. Let them develop a US-style de facto Microsoft business standard and they then become owned by Microsoft.

    We've all seen Windows users circulate simple text-only notes in Microsoft Word .doc files. While it may be annoying to those without .doc capabilities (including users of older versions of Word, itself), it is a beautiful thing from Microsoft's point of view. It perpetuates their monopoly while forcing upgrades among the faithful, all in the same simple act. The widespread use of proprietary formats tends to lead to even more use of those same formats.

    However, as Microsoft's markets in the US approach the saturation point -- and start to recede -- they are faced with a dilemma. Do they try desperately to hold on to as much market share as possible, or do they cash in while accepting -- and accelerating -- the inevitable decline in share?

    I think Microsoft will be increasingly choosing the 'cash in' option as the pressure rises to keep earnings high. The first victims of this gradual policy shift will be business and government users in developed countries with strong IP protection laws.

    Next, in approximate order, comes consumers in developed countries and business / government users in rapidly developing countries -- especially those countries seeking easy access to western markets. Last to pay up will be students and consumers in the poorest developing countries.

    But, for all of you still getting a free ride from Microsoft, the good times will inevitably come to an end. They are simply waiting until you, and your compatriots, are too invested in the knowlege, skills, and standards of Microsoft products to quit. Then, they will charge you.

    If you are an unlicensed Windows user who can't afford to someday become a profit center in the vast Microsoft empire, you should consider the alternatives. I recommend you start by downloading and burning a live Linux CD of Knoppix, booting it up on your Windows box, and trying it out. It's free and since it runs straight from the CD, you don't need to install it on your hard drive.
    mail this link | permapage | score:9011 | -Ray, August 1, 2005

    Space Tyrant: A threaded C game project: First Code

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    First code: This is the first code release of Space Tyrant. This is an early stage of development and, at this point, only implements the listening thread, the two IO threads for each player connection, and a skeletal game logic thread that does little beyond proof-of-concept code.

    The design of the code was discussed in this article so you should probably go back and read that article if this is your first brush with this project.

    The first code release -- what we will be discussing in this article -- is online as spacetyrant1.c. Download it as well as the shell script you’ll need to compile it: makeit1.sh. The script should work under both Linux and Mac OS X. The code will require a single line change to compile under Mac OS X. Search the code for the string OSX to find the line to decomment and the corresponding line to comment out.

    Currently, the program allows multiple people to connect using telnet and echos anything they type to all other connected sessions. Some familiarity with the C programming language will be assumed in this article and those to follow.

    Configuration constants: There are several ‘configuration constants’ defined by #define statements. The key constants and their meanings are:

    MAXTH: This number represents the maximum number of users that can connect simultaneously. This constant is used to set limits on loops and to define the number of elements in various arrays. This number must be a power of 2.

    MAXTHBITS: This is simply the number of bits necessary to form an unsigned int to index into arrays of MAXTH size. This number is used to declare bit fields for use with various items that occur MAXTH times. In the code we use a MAXTH of 256 and since 2^8 equals 256, MAXTHBITS is set to 8. Note that if you change MAXTH, you must make an appropriate change to MAXTHBITS!

    MAXBUF: This is the number of buffers used in various places. For example, the input threads each get MAXBUF numbers of buffers.

    MAXBUFBITS: This number matches MAXBUF in that it is the number of bits necessary to express the number MAXBUF in the same way that MAXTHBITS relates to MAXTH.

    MAXLINE: This is the maximum length (in bytes) that is allowed for network input and output. The IO buffers, for example, are declared to be size MAXLINE + 1. The ‘+ 1’ is to allow room for a terminating 0.

    RADPAD: This is added to MAXLINE to determine the length of a radio buffer. Radio buffers need to be larger than IO buffers since they must allow room for headers.

    Data structures: Next, we declare a struct to contain most of the data associated with each thread. Note that this struct contains no player-specific data; it is used only to contain the data necessary to define an input thread and an output thread used to define one user connection. ‘threc’, as we will call the struct, will be an array with MAXTH elements. It will contain the thread ID of both the input and output threads, the timestamp of the last input from the input thread, the number of the socket descriptor, and various flags and indexes that will be used to coordinate the activities of the input, output, and game logic threads. Look at the code comments themselves for details on the variables.

    Note that MAXBUFBITS is used to declare the size of inndx, outndx, inptr, and outptr. These variables, when incremented past the number of buffers, wrap back to zero, making it easy to implement ring buffers. That is why the MAXBUF number must be a power of 2.

    The thread functions: In this program main() has two primary functions. First, it calls any initialization functions and clears the various data structures and spawns any other permanent threads. Second, it goes into an endless loop of accepting user connections and spawning IO threads to handle the newly connected users.

    The next thread function, gameloop(), has the hard job. It constantly loops though the input buffers, looks for input that needs to be processed, and does it. While looping around the buffers, it also looks for input threads that have gone idle and terminates (‘reaps’) them. Currently, the only input processing it does to call a function named broadcast() with any data it finds in the input buffers. The broadcast() function simply copies the input to output buffers. This bit of processing is for proof-of-concept purposes only and will be replaced by actual game logic as it is developed.

    The last important thread functions, userin() and userout(), exist in multiple pairs to perform network input and output duties for each connected user. The userin() thread reads the network connection and loads data into the next available input buffer (‘inbuf’). It then timestamps it, and goes back to waiting for more input. The userout() thread loops continously waiting for anything to appear in the next output buffer (‘outbuf’). When new data is placed in an output buffer by the gameloop() thread, userout() writes it to the user’s network socket.

    Note that because userout() and gameloop() loop continously, they sleep after each ‘idle’ loop. That is, when they pass through their logic loop and find no actual work to do, they call the usleep() function to sleep a tiny fraction of a second. This sleeping prevents them from consuming unnecessary processor cycles.

    [Update, June 25, 2005: A Space Tyrant home page has been created as a central index to the various ST articles, links, and files.]
    mail this link | permapage | score:8998 | -Ray, March 27, 2005 (Updated: June 25, 2005)

    MiniLesson: An introduction to Linux in ten commands

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    This tutorial is the first in a series of introductory Linux lessons. This first article will cover navigating around a Linux filesystem along with a brief passage -- with examples -- on using ten of the most essential GNU/Linux commands.

    You should have access to a Linux system in order to perform the example commands as we progress through the tutorial. If you don't have a dedicated Linux box, you can use a Live Linux CD-ROM-based distribution such as Knoppix. Knoppix will let you run Linux directly from the CD without modifying anything on your hard drive.

    Once you're logged in to a Linux system, open a terminal session. Each of the commands covered here will be typed directly into a command line terminal window. Under Red Hat Linux, terminal is found in the 'system tools' section of the menu. (Your system may, alternatively, have a terminal program called 'konsole', 'xterm', or 'shell'. Look around your system for a menu with 'tools' or 'utilities' in the name if necessary.)

    pwd
    The first command we will use is 'pwd' -- which stands for 'print working directory'. The pwd command shows you your current position within the Linux filesystem. The position is known as your 'current working directory'. Type pwd now. The example below shows my command prompt and the pwd command followed by the output from the pwd command:
     [rayy@barton0 rayy]$ pwd
    /home/rayy
    [rayy@barton0 rayy]$
    From the output (/home/rayy) we can tell that I am in my 'home directory' -- the directory where I keep my personal files and the directory where I always start out in a new session.

    ls
    The ls command lets you list files. For example, here is the (shortened) output of an ls command on my system:
     [rayy@barton0 code]$ ls
    artdir countdir machine
    tsardir sortdir
    [rayy@barton0 code]$
    Alternatively, you can get a 'long listing' that shows file sizes, timestamp, ownership, and permissions as follows:
     [rayy@barton0 code]$ ls -l
    drwxr-xr-x 2 rayy rayy 4096 Feb 3 2002 artdir
    drwxr-xr-x 2 rayy rayy 4096 Feb 3 2002 countdir
    drwxr-xr-x 2 rayy rayy 4096 Feb 3 2002 machine
    drwxr-xr-x 2 rayy rayy 4096 Feb 3 2002 sortdir
    drwxr-xr-x 2 rayy rayy 4096 Feb 3 2002 tsardir
    [rayy@barton0 code]$
    You can also supply a target directory to the ls command. For example, to view the contents of the /tmp directory, I enter the following:
     [rayy@barton0 code]$ ls /tmp
    flp kde-rayy mcop-rayy
    [rayy@barton0 code]$
    For more information on the ls command you can reference the manual page for ls with the following command:
     [rayy@barton0 code]$ man ls
    cd
    This next command, 'cd', lets you change your current working directory. for example, you can change your current working directory to /usr/bin by entering the following command:
     [rayy@barton0 rayy]$ cd /usr/bin
    [rayy@barton0 bin]$
    Note that after I entered the cd command, my command prompt changed to reflect the change in the last node of my current working directory. Your command prompt may not be configured to do that.

    Change your current working directory to /usr/bin now and enter the ls command.
     [rayy@barton0 code]$ cd /usr/bin
    [rayy@barton0 bin]$ ls
    addr2line mcheck
    addr2name.awk mcomp
    addresses mcookie
    .
    .
    .
    [rayy@barton0 bin]$
    The preceding is a partial listing. There are many, many files in the /usr/bin directory on most Linux systems.

    file
    If you have a background in Windows or are familiar with DOS, you are used to file extensions that signify the file type. Linux (and Unix) have no such requirement. That is, an executable program can be named anything. Therefore, a handy command is supplied with Linux named 'file'. For example, I have a file named 'sample.c' in my code directory. I can learn a bit about that file by entering the following command:
     [rayy@barton0 code]$ file sample.c
    sample.c: C++ program text
    [rayy@barton0 code]$
    Alternatively, I can use the '*' wildcard -- which represents all filenames -- to examine all of my code files at once. The following is a shortened example:
     [rayy@barton0 code]$ file *
    bbsdir: directory
    code.tar: GNU tar archive
    genart.c: ASCII C program text
    sample.c: C++ program text
    xor: ELF 32-bit LSB executable
    [rayy@barton0 code]$
    The file command can be very useful to avoid minor annoyances -- such as when using one of the following three commands.

    cat
    The cat command is useful for concatenating multiple files -- or just for dumping a single text file to the screen. Before you use the cat command to dump a file to the screen, use the file command to make sure it's some variety of text file such as ascii text, commands/text, C source code, html/text, etc. The following is a shortened example of using file and cat to identify and dump a text file:
     [rayy@barton0 code]$ file xor.c
    xor.c: ASCII C program text
    [rayy@barton0 code]$ cat xor.c
    main()
    {
    int x;
    unsigned char buff[128],
    .
    .
    .
    [rayy@barton0 code]$
    more
    The more command is useful when a text file is larger than a single screen. The following is a shortened example of using more to view a large C program:
     [rayy@barton0 code]$ more xor.c
    main()
    {
    int x;
    unsigned char buff[128],
    .
    .
    .
    printf("n%sn",buff1);
    printf("n%sn",buff2);
    }
    --More--(29%)
    Note the '--More--(29%)' at the end of the screen. That means that 29% of the file is above that line, implying that another 71% of the file is below. Press the space bar to page through the file, a screenful at a time. Press the b key to back up. If you finish looking before reaching the end of the file, press the q key to quit.

    grep
    The grep command, short for 'get regular expression and print', is useful for finding occurances of a particular string in a text file. To find the 'printf' statements in the example C program above, enter the following command:
     [rayy@barton0 code]$ grep printf xor.c
    printf("n%sn",buff1);
    printf("n%sn",buff2);
    [rayy@barton0 code]$
    The grep command has far more capability than I describe here and, as usual, enter
     [rayy@barton0 code]$ man grep
    for more information.

    cp
    The cp command will let you copy files. Unlike the commands used above, this one includes a hazard; if you copy filename1 to filename2 and filename2 already exists, you will destroy the original filename2 file. Use cp with caution!

    To make a duplicate copy of my xor.c file I could enter the following command:
     [rayy@barton0 code]$ cp xor.c xor.c.bak
    [rayy@barton0 code]$ ls xor.c*
    xor.c xor.c.bak
    [rayy@barton0 code]$
    Note that the cp command returned no output -- I had to enter an ls command to see the results of the copy. [By adding the * wildcard to the original filename, I asked for a listing of all files that started with xor.c -- including those with no additional characters in the name.]

    rm
    The rm command is used for removing files. To remove the duplicate file I created in the cp command example, I would enter the following:
     [rayy@barton0 code]$ rm xor.c.bak
    [rayy@barton0 code]$ ls xor.c*
    xor.c
    [rayy@barton0 code]$
    Again, note the absense of any feedback from the rm command. I had to enter an ls command to verify that the xor.c.bak file had really been removed.

    As with other commands, rm can remove multiple files at once when used with wildcards or with the -r (recursive) option. See the man page for more information on rm.

    mkdir/rmdir
    Ok, this is really two commands, but they are complementary. Use the mkdir command to make a new directory and use the rmdir command to remove an empty directory. For example:
     [rayy@barton0 tmp]$ mkdir testdir
    [rayy@barton0 tmp]$ ls
    testdir
    [rayy@barton0 tmp]$ rmdir testdir
    [rayy@barton0 tmp]$ ls
    [rayy@barton0 tmp]$
    In the preceding series of commands I first created a new directory named 'testdir'. I then used the ls command to verify its presence. Then, I removed 'testdir' and verified that it was gone by using ls again.

    For more information on the commands covered in this article, take a look at the general commands man pages over at the LinuxQuestions.org website.
    mail this link | permapage | score:8994 | -Ray, February 19, 2004 (Updated: April 18, 2007)

    Tutorial: Linux Dialog Boxes

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    Dialog lets you create dialog boxes from Unix/Linux shell scripts...
    'dialog' is a utility for building console-based 'front ends' in UNIX like operating systems.

    In this brief tutorial I am mentioning the usage of few important basic controls available with this 'dialog' utility and later I have created a very simple front end application in UNIX bash scripting using dialog.
    read more...
    permapage | score:8993 | -Ray, January 1, 2010

    Install Liferay 6.0.5, Tomcat on Ubuntu 10.04

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    Liferay Portal is an enterprise web platform for building business solutions that deliver immediate results and long-term value. Get the benefits of packaged applications and an enterprise application framework in a single solution. read more...
    permapage | score:8968 | -falko, September 7, 2010

    Apple to Intel move no threat to Linux

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    John C. Dvorak's recent Marketwatch commentary, 'Linux is likely the big loser', is completely off base. His fundamental mistake is to assume that 'the X86 platform' is more appealing than the freedom of Open Source and that the x86 processor is the important consideration for development:
    It's likely that developer interest will wane when Apple is fully engaged on the X86 platform. While Apple ran on the PowerPC chip the amount of developer effort in the Open Source camps was nil. But now that Apple is using the same processor as everyone else, targeting the Macs will now be an easy decision to make. This will be at the expense of Linux.
    No, the Apple announcement doesn't mean that you'll be able to run OS X on a Dell. In the unlikely event that the Intel-based Macs are insufficiently different from PC's, Apple will build in additional hardware security features. Mac OS X will check for these features and will refuse to run in their absence.

    Realistically, Apple will not make generic PC’s nor will the upcoming Intel version of Mac OS X run on non-Apple hardware. The new Apples will be just as proprietary as the PowerPC-based Apple hardware -- and just as distinct from the generic 'PC market'.

    Above all, Apple is still a hardware company and a switch to commodity hardware -- or even making their new computers PC compatible -- would be a far more dangerous business risk than simply switching CPU architectures. Apple is not changing their business plan. They are changing their processor architecture and supplier only.

    Try as they might, even Microsoft can’t stop Linux. And Apple isn't even trying.

    The Apple switch to Intel processors is quite simply irrelevant to Linux.

    Meanwhile, Apple's move makes sense from a market perspective. And it's not about clock speed or raw performance as some have suggested -- although those considerations are important. The obvious reason that rules out performance as the overriding consideration is simply that they didn’t choose the AMD Opteron for the Power Mac.

    Rather, it appears that this strategic shift is (almost) all about laptops (and perhaps Mac Minis -- which technologically are just battery-less laptops in a new form factor). Laptops are now outselling desktops -- and that trend will increasingly drive hardware makers' profits. And at Apple, that trend may be even more important than in the general PC market. If this were about performance and price/performance at the high end, the partner would be AMD. This move is primarily about power-per-watt at the low end, hence, Intel.

    Of course, we mustn't forget that the high-end systems will be migrated last, possibly more than two years from now. That gives Apple plenty of time to add a second partner if Intel's vast resources are unable to rein in AMD on the performance front. And, obviously, a move to AMD at that point would be a small technical task compared to the PowerPC-to-Intel switch.

    With some luck and continuing success at the high-end, AMD could still get a major design win out of this transition.
    mail this link | permapage | score:8968 | -Ray, June 9, 2005 (Updated: August 1, 2005)

    Space Tyrant: A multiplayer network game for Linux

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    Since the last release of Space Tyrant, it has gained some actual game-like functionality. The new code can be downloaded from st2.c. Download it as well as the shell script you’ll need to compile it: makeit2.sh.

    It’s now possible to connect to the game via telnet and to create an account, log in, and be issued a ship. Once you’re logged in, there is a universe to explore filled with ports for buying and selling goods and planets for scooping free goods. From those trading activities you can earn money, called microbots. Other than trading to earn more money, you only use your microbots to buy fighters -- which you can use to attack other players or the neutral fighters that guard some sectors.

    The neutral fighters are only good for parking under while you’re not playing. They afford a little bit of free protection for your ship since no one can attack you until they first destroy the neutral fighters. Note that you can attack other players whether they are logged in or not and any fighters with their ship will automatically try to defend them.

    Each player starts out with a specific supply of fuel, called antimatter. Each minute a small amount of additional antimatter is issued by a function called updatefuel(). If you’re not logged in, fuel just accumulates in your ship. This continuous allocation of fuel makes Space Tyrant a type of turn-based game. Unlike traditional turn-based games, however, you can play your fuel all at once or a little at a time and completely independently of how and when other players play.

    You can also talk to other players on the radio. There is only one channel so everyone who is logged in hears everything that is said on the radio.

    The game isn’t yet playable in any reliable sense, however, because it doesn’t yet back up and reload the data from disk files. The software creates an instance of the game when you run it and it remains running until you stop it or the system goes down. There is also no way to establish a time limit on a game.

    That’s pretty much the extent of the functionality changes. Now, on to the code.

    First, there is a login function. That function looks in the player database struct and, if the player name doesn’t already exist, it creates an account there. If the name does exist, it prompts for a password, matches it against the stored password, and logs you in if the two match. There is not yet a way to change your password.

    Once a player is logged in, he is faced with a sector description and a ‘choice:’ prompt. Any character that the player types at this prompt is immediately acted on as if it were a command. There is a string called ‘commlist’, short for command list, containing the letters and characters that are used as commands. A function pointer array, ‘fp[]()’, is used to store the locations of the command functions. Another function called ‘commscan()’ looks up the command letter typed and returns an index into the fp[]() function pointer array. This combination of the commlist string, the commscan function, and the fp function pointer array constitute the command processing loop of the game, as shown below:

    userndx=commscan(
    tolower(
    threc[th].inbuf
    [threc[th].inptr][0]
    ),commlist
    );
    result=fp[userndx](th);

    These lines are embedded in a loop where each user’s input thread, represented by the variable ‘th’, is examined for new input. The new input arrives in string called inbuf. Since each thread has several buffers, an index called inptr is used to keep track of which one is currently being processed.

    And, as described above, commscan is used to extract the appropriate function index and place it in a variable called ‘userndx’. Then, userndx is used to index into the fp function pointer array and the thread index (th) is passed to the appropriate command-processing function.

    There’s a small amount of misdirection in that first line but, once understood, it becomes trivial to add additional commands. Basically, you just need to replace the placeholder function, ‘nullrtn’, with your new function name adjacent to the command letter you select in the fp[]() definition list.

    The new functions are discussed below.

    makemap()
    In keeping with the evolving game nature of this project, several actual game functions have been added. The first new function, makemap(), builds a 20,000-sector single-galaxy universe and populates it with objects. By changing the GAMESIZE constant, you can build a universe of arbitrary size, but make sure you don’t try to build a universe so big as to consume too much of your system’s memory. I’ve tested universes of up to 1,000,000 sectors, which seem to work just fine. The makemap() function randomly puts ports, planets, fleets of neutral fighters, and nebulas in various sectors throughout the universe, and interconnects the sectors with randomly-generated one-way ‘warps’. Note that planets and ports are randomly given varying productivity's and random initial inventories of our three commodities: Iron, Alcohol, and Hardware.

    Note that makemap() builds each sectors array of six warps, sorts them into ascending order, and then looks for duplicate warps. If any duplicates are found, it decrements the loop-controlling variable and simply rebuilds that entire sector from scratch. The sorted warps are a convention that we will maintain throughout the project. Each new galaxy type that we add in the future will adhere to that convention and other functions (and users) will be allowed to assume that warps are in ascending order.

    command()
    We have added a function to simply list the implemented commands and a short line of description. For now, the function is attached to the command letters ‘?’ and ‘H’ via the function pointer array and the commlist array. This function is mostly useful to illustrate a design limitation. The output of any single sprintf buffer-building function cannot exceed the MAXLINE buffer size constant. This function produces a single buffer out output very near the current 511-byte limit and will soon have to be split to produce two buffers of output. Assuming, of course, that we don’t increase the MAXLINE buffer size.

    jettison()
    The ‘J’ command activates the jettison() function. It’s only purpose is to dump any cargo out of your cargo holds. It illustrates the method we use to let a function that requires multiple characters of input -- or simple confirmation -- to temporarily turn off command processing and send the next character of input back to it. Jettison requires confirmation so that you don’t accidentally dump your cargo just by hitting the J key. (Since all commands operate as ‘hot’ keys you do not have to hit the [Enter] key to activate a command -- each command immediately executes as soon as you press a key.)

    Each command function has the ability to set the thread’s control variable to it’s own command letter. That way, the command processing loop can simply check ‘control’ pass the next buffer of input directly to whichever function is indicated.

    warprtn()
    jumprtn()
    The warprtn and jumprtn functions process requests to move to another sector. warprtn() processes the commands 1, 2, 3, 4, 5, and 6, which represent a user’s request to move to the first through the sixth sector number in the warp list, respectively. jumprtn() processes requests to move to a randomly selected sector in the warp list via the ‘-’ (or ‘=’) key. jumprtn() also implements commands to move to the next larger sector, the next smaller sector, as well as the largest and smallest sector number via the ‘.’, ‘,’, ‘>’, and ‘game design and the programming model. The second article discusses the IO handling code and more of the details of the programming model.]

    [Update, June 25, 2005: A Space Tyrant home page has been created as a central index to the various ST articles, links, and files.]

    [Update, March 21, 2007: Space Tyrant now has a website of its own!. This site is new but growing and will be the quickest way to find new information and code on the Space Tyrant project.]
    mail this link | permapage | score:8967 | -Ray, May 30, 2005 (Updated: March 21, 2007)

    FreeBSD 8.0: First Look

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    A look at the newest FreeBSD distribution...
    The ZFS file system is included in FreeBSD 8.0 and from previous experience I've found it to work very well. However, my little server didn't really have the resources to properly experiment with it. For systems with enough RAM and disk to justify its use, I highly recommend taking a look at FreeBSD's ZFS implementation - for the snapshots feature, if nothing else. Being able to restore files without reaching for separate backup media can be a wonderful time saver.
    read more...
    mail this link | permapage | score:8962 | -Ray, December 8, 2009

    Alternative operating systems

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    The ten best alternative OSes, none of which are from Microsof or Apple, nor are any based on Linux. Operating systems covered are:
    • GNU/HURD (RMS' never-quite-done free OS, predates Linux(!))
    • JNode (written in Java)
    • FreeVMS (DEC's famous VMS)
    • DexOS (tiny, console-like GUI)
    • Inferno (distributed, device-sharing)
    • KolibriOS (MenuetOS fork, tiny, written in Assembly)
    • OpenBSD (a BSD variant specializing in security, correctness)
    • AROS (Amiga Research Operating System )
    • ReactOS (Windows clone)
    • Haiku (BeOS clone)
    From the article:
    Big companies can grow reticent to change, slow to move and adopt new technologies. Features must be escalated through approval bodies, management and bean-counters. Hobbyist projects don't have those commercial pressures and can experiment freely.

    It might seem audacious to claim that the next Windows is cooking in some part-time coder's house, but it's nothing new. Microsoft's OS empire started with the purchase of QDOS, which stood for 'Quick and Dirty Operating System'. Apple didn't create Mac OS X out of thin air, but took an open source kernel and some BSD code (grounded in academia) to get the foundations of its operating system working.
    read more...
    mail this link | permapage | score:8959 | -Ray, March 16, 2011
    More articles...
    Abstract Art Prints by Ray Yeargin

    Selected articles

    Microsoft to push unlicensed users to Linux

    Graffiti Server Download Page

    Space Tyrant: A threaded C game project: First Code

    MiniLesson: An introduction to Linux in ten commands

    Shadow.sh: A simple directory shadowing script for Linux

    Linux dominates Windows

    The Real Microsoft Monopoly

    Currency Traders Telnet Game

    Why Programmers are not Software Engineers

    How to install Ubuntu Linux on the decTOP SFF computer

    Why software sucks

    The short life and hard times of a Linux virus

    The life cycle of a programmer

    Programming Language Tradeoffs: 3GL vs 4GL

    Librenix T-Shirts and Coffee Mugs!

    Missing the point of the Mac Mini

    Space Tyrant: Multithreading lessons learned on SMP hardware

    The Network Computer: An opportunity for Linux

    VPS: Xen vs. OpenVZ

    Beneficial Computer Viruses

    Apple to Intel move no threat to Linux

    Mono-culture and the .NETwork effect

    Scripting: A parallel Linux backup script

    Hacker Haiku

    No, RMS, Linux is not GNU/Linux

    Tutorial: Introduction to Linux files

    Space Tyrant: A threaded game server project in C

    Space Tyrant: A multiplayer network game for Linux

    The Supreme Court is wrong on Copyright Case

    Closed Source Linux Distribution Launched

    Apple DIY Repair

    Linux vs. Windows: Why Linux will win

    Download: Linux 3D Client for Starship Traders

     

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    Articles are owned by their authors.   © 2000-2012 Ray Yeargin