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this page: Linux and OSS Command line fun openSUSE 11.0 Custom boot themes for openSUSE & KDE Who's the best? The Prophetic Voice of Linux Archive: Virus scanning for Linux |
me Digital Continued On this page you will find extended versions of some items on the main meDigital page. To continue surfing this website please return to meDigital first. |
| Linux
and Open Source Software (OSS) First published 13/04/2008
Updated 10/09/2009 One of the wonderful outcomes of this movement for freely shared software is Linux, initially written as an operating system for PCs, but by now applicable to virtually anything running a microchip. In the same flow an enormous amount of open source applications has become available, often for Linux platforms, but also for Windows or Mac. All this wealth offers more than enough for office use, education, multimedia, mobile computing and even gaming. |
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Intermezzo for newbies
(*please skip as appropriate): a mini lay course in computer architecture.
So Linux is a bridge between hardware and applications. But remember that none of the three layers can operate without the other two. There is a continuous and busy two-way traffic. |
| Your own computer? Now if you buy a new computer, something curious happens. You pay at the till and become the proud owner of all the bits, bytes and bolts inside the box. But alas, that's only layer 1 and it will not work without OS and apps, layers 2 and 3. Conveniently enough these were already pre-installed. You also payed for them. But... if you read the software licence (EULA) carefully, you will learn that you own nothing on layer 2 and 3. You only payed for the use of the software and you are strictly forbidden to do anything about it, or even look under the hood to watch how it works. The source code is absolutely closed and proprietary. And it comes usually with a 'guarantee' that it will work for 90 days, provided you do not add anything to your system. So after your have saved your first documents, checked your email or you added anything useful like a virus scanner, you'll just have to wait and see what that 'guarantee' is still worth. Now I would call that a Dutch treat. But hey, all companies are customer focused nowadays, aren't they? So all you have to do at the till is to say that you are happy to buy the hardware, but without the software. It's not that difficult to install an OS and the apps of your own choice. Well, that is possible, but chances are high that you end up empty handed. It's the whole bundle, or nothing. Free enterprise as opposed to free choice. OK, you have accepted this no-choice deal. The new computer is safely installed, up & running. Now you happen to be one of those people who have their own particular wishes for applications. Perhaps you would like to have some functions added or removed, or you would prefer another 'look & feel', or it would be useful if some applications could work together. If you were a programmer, you could think of making something yourself. Unfortunately that is an absolute no-go. The EULA forbids to change anything. If you do, you become a hacker, something like an enemy of the state... Of course, if you yourself (like me) have no clue at all how to program, still others might be able to change or improve software in a way you could benefit from. But as long as the software is proprietary, it is impossible. It is as Henry Ford once said, 'They can have my cars in any colour, provided it's black.' |
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What's the alternative? First of all, an operating system that enables users to organise things as much as possible in the way they want it. Not 'what you see is what you get' (WYSIWYG), but 'what you get is what you want' (WYGIWYW). In that case everything you do, you do at your own risk, of course, so if you don't know what you're doing, don't do it. Yet the simple fact that things can be changed opens up a world of possibilities. Linux is such an open source OS. Its logo is Tux, the penguin. On a Linux platform a huge amount of Open Source Software (OSS) will run. Most of it come with some version of the GNU Public Licence. |
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Second intermezzo
(*don't skip, you may not know this).
In a relatively short time Linux has evolved from a private hobby into one of the most flexible and stable platforms in the OS world. |
| Why Linux? But OK, you're just a common user. Why go Linux? What's the deal for you? First of all that you can have your computer running nicely and easily without paying anything like you would be charged for by Microsoft or Apple. And equally free you get all these wonderful applications that come with the distribution, including office suites, internet tools, multimedia gadgets, graphics and video editors, games etc. Basically, anything you can do on Windows has a free, open source alternative of equal or better quality. And if you have specific Windows applications that you really need, you can often run them under Linux using Wine. There are still some problems with getting some particular hardware to run properly (some scanners for example), but every month new device drivers appear and hardware manufacturers seriously start to look to Linux for saving costs. The question is rarely 'can I do that on Linux?' but instead 'which application will I choose this time?' And if you would like to try some programming yourself, Linux is definitely your platform. |
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Governments
in Germany
and France have been
migrating a substantial part of their servers and desktops
to Linux and OSS for more than five years now. The main reasons are
saving costs, security, stability and freedom of choice. China, the
biggest
market anywhere, puts a strong emphasis on Linux and OSS. To provide
less wealthy countries with computers there is the One
Laptop per Child Project, which runs a technically
revolutionary design on Linux. Disputes between Windows and Linux adepts or fans of open source against closed source are notorious and very hard to describe in a neutral way. It probably proves that some computer science is rather religion... To summarise the advantages of a Linux system: - all software is free - meaning: you don't (have to) pay for it - and: you are welcome to extend, improve or correct - Linux is very stable and safe (no viruses) - Linux is particularly good in multitasking and networking - the amount of nice software extends every month - and every user can customise a whole lot. |
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Have a look around Want to have a look at Linux? Be forewarned: the amount of information is huge. Just start on a general site, have a look at major distributions (Ubuntu, Debian, openSUSE, Gentoo, Fedora, Mandriva, Slackware), read a magazine. Alternatively, you can try Linux by running it from a Knoppix Live-CD, which will not change a bit of your existing PC system. New PCs with Linux pre-installed (instead of the Other OS) are starting to appear. Dell is beginning to see the Light with Ubuntu pre-installed on a PC and a laptop model. The Asus Eee-PCis a very interesting and affordable new design running Linux (unfortunately in 2009 caged again by M$, but you can still easily install Ubuntu on it). The classic big ones like IBM (Lenovo) or Hewlett-Packard start to include Linux as well. In the UK DNUK supplies anything from desktop to a complete network with the Linux distro of your choice. But you can also buy an empty PC system and install Linux yourself. All distros mentioned above are as easy to install as Windows, and you will have all your applications installed in one move. Have fun! Back to top |
| Command line
fun NOTE: I work with openSUSE 10.2 and the applications that can be found in this distribution's connected repositories. Basically the command line is the same in any distro, but please use your own common sense if something is a bit different than described below. |
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Manual software installation First published 13/04/2008
Sometimes there is not a precompiled package available for an application, such as RPMs or DEBs. Instead you get a compressed archive with source code, aka 'tarball'. You can learn that from the extensions: tar.gz or tar.bz2. What to do? Assuming that the tarball is built as it should, do the following. 1. Unpack the archive in the (temporary) directory where you have put it:
(for a tar.gz:) tar
-xzvf [full_name_of_tarball]
(for a tar.bz2:) tar -xjvf [full_name_of_tarball] TIP 1: If you want to learn all options for tar, type tar --help | less
TIP 2: Usually there is a file like README or INSTALL in the unpacked archive. Read it before you continue! It will probably give you information you need. You may even have to skip all good advice below... 2. Configure, compile and install the source code from within the unpacked directory. You can put all commands in one line (using && and sudo), but I like to do it step by step in case something does not work. That can certainly happen. In that case read the error messages and see if they give the right clue to solve the problem.
cd
[path_to_unpacked_source_code]
./configure
make
su (root password will be asked)
make install That should work. If all went well, you can delete the directory with unpacked source code now. Back to top |
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Making backups First published 15/04/2008
Updated 14/05/2008 I'm a backup freak. There's a reason, of course. In days long gone, as a fresh project assistant to my university's Church History Department, one of my first actions was to accidentally delete the document we were working on. That is: 1,000 pages of text, 2 years of work, and we still worked under DOS 5 - no recycle bin, remember? And the full academic staff was still fully unaware of a phenomenon called 'backup'. Another assistent happened to know the new undelete command. Yes, God exists! Ever since I've backupped frantically, and it has saved my day more than once. On my computer I backup my home directory very frequently to a second harddisk and once a week (at least) I backup the backup to an external harddisk too. In my Windows days I have used several freeware tools for this purpose, and I also tried the various attempts for backup apps that came with Windows. The latter were usually crap, some of the freeware ate all of my resources while active, almost freezing the system. And to make automatic backups, I had to pay, every year again. How has my heart rejoicing once I migrated to Linux: it knows everything you need even before you ask... OK, how to backup? There are several tools, but I prefer rsync. At the command line you simply type 'rsync' to run it. It allows you to synchronise directories or files between different partitions or different computers within a network. You can use it for local backups, but also to keep a remote target updated, eg. your webserver. To learn rsync options type: rsync --help | less
An example of how you backup your home directory to a backup location (type all on the same line): rsync -r -t -p -o -g
-v --progress --delete -u --modify-window=1
[full_path_to_home_directory] [full_path_to_backup_directory]
Note that if the path ends with a directory, a trailing slash ('/') is mandatory; if if ends with a file, don't type a slash. Read the help information to figure out what all the options are for. In style you do that this way: man rsync
(and to close it:) q If you know how to make a cron tab, you can add the same command there and set cron up to do it automatically for you. Warning: backing up a large home directory will claim maximum resources for 1-2 minutes, depending on your hardware. Linux will not allow your system to freeze, but other applications will slow down. |
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Lazy ways There is one more way to make rsync easy: install and use grsync. That is just a graphical frontend to rsync. It saves you a lot of typing and you can keep your commands as sessions. Back to top |
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openSUSE 11.0 First published 21/11/2008
So, what about openSUSE 11.0's peculiarities? Well, most things run just as well or better as they did on earlier releases; some things need extra attention; a few things don't do what you expect them to. And there are always some puzzling moments. Plusses There are quite some plusses compared to previous editions. The system start has greatly improved. openSUSE 11.0 runs smoothly and very stable and with every new update more remaining bugs get dealt with. The YaST Package Manager has had a good overhaul, which made me decide to use it again. On openSUSE 10.2 I used Smart Package Manager because it was much faster than the YaST tool, and cleverder in dealing with dependencies. But with version 11.0 that's history: setting up repositories is really easy, since the most used are already preconfigured. Just check the box and go. I think the graphical performance has also improved with version 11.0, but technically I'm not an expert on that. Some applications seem to run better, although that may be a coincidence. Meanwhile Wine has clearly matured and I am also pleased that I can actually use the HP Toolbox now for print management. Careful! Yet there are a few caveats, the greatest being the choice between KDE 3.5 and KDE 4.0. Initially I tried the latter. Looks impressive and most promising, but it is very much work in progress still. Many applications are not really ready for it. So I soon started to fumble and decided to reinstall with KDE 3.5, awaiting at least KDE version 4.2 before I give that another try. To be honest, this is what openSUSE advises. But even if you opt for KDE 3.5, then still some parts of KDE 4 are installed, and I think that does confuse some applications. Also, when updating software, I learned to be careful with some applications: some latest versions seem to be intended for KDE 4 and do not work properly if KDE 3.5 is still running. This seems to be the case with Krusader, KRename and RSI Break. They all run perfectly, but I had to lock their versions in YaST Package Manager. An annoying issue is that KPilot refuses to see my palmOne Treo. I've tried a few things, and searched the web a bit, but I've given up. Perhaps an extended search on the forums will provide a solution, but for the time being I synchronise the device on the other computer, running openSUSE 10.2, and then synchronise Kontact over the home network. Kontact, by the way tends to produce error messages about lock files on system halt. Once restarted the problem is usually resolved, and all I need to do is remove old lock files from time to time. But this is not an issue specific to openSUSE 11.0, and I suppose it's a known bug. Just like the one that make KMail incorrectly name new mail in the Inbox, which puts KBiff off its stride... KlamAV kept producing error messages. Since it does slow down my system anyway and it is not really essential for security, I just removed it. ClamAV does run on retrieving and sending email, so no problem. Puzzles And there are of course some wee puzzles. Why did gFTP disappear from the repositories? OK, FileZilla is a great alternative, but I was used to gFTP's simplicity. The same for Kooldock: I really like that tool and immediately missed it in the repositories. So, I've installed it from source and again I can enjoy this Mac OSX-like dock utility. Back to top |
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Custom
boot themes for openSUSE & KDE First published 28/05/2008
Updated 21/11/2008 There is a lot you can customise about the graphics during your system boot. Information about it, however, is a bit hard to find or simply confusing. But at last I found out how to do the job and I happily share my knowledge. It has become a long story. Here is a brief summary. Although this is all based on my own platform with openSUSE/KDE, it may also be useful for others running Linux. Perhaps even Windozers can learn something... All is tested and found working for openSUSE 10.2/11.0 and KDE 3.5.7/3.5.9. Boot process When you switch on your computer the BIOS will run automatically, checking basic hardware setup. Then it activates the bootloader, a wee piece of software that checks partitions and file systems, and knows how to find an active operating system. That, in turn, will load the kernel, which will start up the system. Finally the desktop manager will open your desktop. Depending on your hardware and on how much you have installed, the boot process can take a couple of minutes. Graphics during boot So, why not look at something nice, or useful, or funny while waiting to start working? Every step of the boot process has something graphical on offer, although, until the kernel is fully loaded, that is pretty limited. Once the desktop manager gets active, you can add quite some eye-candy. Of course that will slow down the startup process, but that's less annoying if you can see something you like... I admit, it is a bit of a circular argument, but who said computers are rational machines? In the 21st century we have definitely evoluated to the level of Homo Ludens, the playful human... So, what did I change about it? The pictures give an impression. My BIOS has an adapted logo (though that's not the merit of Linux). And for the rest I basically added my main desktop wallpaper to the various steps of the boot process. In grey tones as long as the X server is not up, and in colour once X Window has started. In a separate article (PDF, 1.1 MB, updated) I explain in detail what happens during boot, what you could customise and how to do that. Back to top |
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Who's
the best? First published 26/10/2008
Updated 17/11/2008 'Who's the best' is an old game, rooted in ancient Germanic paganism. The warrior-like society of Europe AD 100 is still alive. We call it Western civilisation. And thus, even in the most democratic environments, such as the open source software (aka OSS) community, there are unlimited fights about 'who is the best' issues. You may have noticed the feuds between Microsoft (aka M$) and Linux (aka Tux) fans? They are endless, boundless and often pointless. So I rather skip making any contribution to this silly game. Instead I will just explain why I like working on a Linux platform most. Think positive, man! Linux explains Documentation can be the bottleneck of an application, or an operating system. It's true, that also goes for a range of Linux apps. However -- apart from the man pages, info pages, help texts, manuals or tutorials that do or do not come with the software -- there is always this huge resource of the wider Linux community. So even if a particular project is not too good in providing answers, there's almost always another way to find out. Every distro has its own Wiki, Community, Forums etc. The Linux Documentation Project, Google Linux Search, Linux Magazine, Linux HQ, Linux Questions, and hundreds of other websites provide additional support. There is so much information that you often have a big job sorting out the pieces you actually need. As opposed to the other OS, where as a rule you are not supposed to know what’s under the hood… Linux provides for my every need To start with, you can choose the distribution that best suits your preferences, but then you can still customise, configure, shrink, extend or whatever to adapt your installation to what you actually need. A small installation on some older hardware or a full-size one on the latest gaming monster, a server install without GUI for security and speed, your own webportal, Linux embedded etcetera. Once installed you can further tweak your system and your desktop environment down to the last bit, if you want. You can swap your boatloader if you like, change your desktop manager on login, setup remote access really easy, make your system as closed as Fort Knox, whatever. As opposed to the other OS which limits your choices to what they think you should and which generally cannot be made secure at all… Linux offers console power In a way it seems old-fashioned, but in fact it is a huge contribution to the system’s power and stability: behind everything running on a Linux platform there is still this basic command-line environment (the old folks may remember DOS), and it is strictly modular in structure. Multitasking, networking, encryption, security, permissions -- all vital processes and protocols run independently from the graphical layer. As opposed to the other OS where blue screens are ever recurrent and you need to reboot after every software installation… Linux manages my packages One of the joys of a Linux distribution is the way it handles software installation and updates. It's all done with one and the same package manager. Once you have set up the repositories in which to search, you can install, update or remove anything available using one clear interface. Not just the OS elements, but also fonts, applications, libraries, utilities etc. The packages are especially built for your particular distro, so you don't need to worry about dependencies or conflicts: the package manager will sort it out, or tell you if it cannot be resolved. My openSUSE 11.0 has greatly improved its YaST Package Manager, so it's really easy to set up the repositories and other sources, and it's much faster in updating these. The Ubuntu varieties use Synaptic, which is even faster and easier, but Smart is another one that can be used across all of these distros. And of course, you can always install from the command-line too, if there is only a source tarball available. As opposed to the other OS which only updates itself and not the applications, for which you will have to visit loads of separate websites… and pay, of course... Linux has a solution for everything For almost any task you would want to perform on your computer Linux and the OSS community can provide. Internet, email, office, accounting, graphics, video, music, telephone, messaging, groupware, networking, web development, databases, education, games, programming, security, system administration -- it's all there, free as in free speech & free as in free beer. And even if you need this one application that is designed for the other OS only, you can often run it using Wine. Or you can opt for hardware virtualization and run a Windoze node from your Linux platform. As opposed to the other OS that even refuses to see any other OS on your PC and makes you pay again and again for every software extension… Linux is safe The system of permissions which is part of the very core of any Linux (or UNIX) system is a very safe starting point. No alien software can possibly run on your computer unless you specifically allow it to. So you don't need a virus scanner -- I do run one to keep an eye on my email, only as a courtesy to others who still run Windoze and to whom I forward messages. The firewall on a Linux system is integrated into the kernel and will start even before the network is up. Spam detection is just the same as on a Windoze machine (so it's not perfect). If you want you can easily tweak the security settings to meet your particular needs, eg. by restricting a user's access to files or software. As opposed to the other OS that is basically accessible to anyone who knows a bit more than the basics and will run anything executable with the blink of an eye… OK, that's enough praise, I guess. What are my favourite applications? Well, just the major ones: Konsole to emulate a
terminal;
OpenOffice.org, especially for its skills to read different formats & to produce PDFs; Scribus for DTP (a bit limited, but no worse than Publisher); Kpdf to read PDFs; Kontact as PIM, with KMail, KOrganizer, KAddressBook and Akregator; Basket for desktop notes; Amarok (plus lyrics scripts!) for music, preferably OGG, but of course it eats anything; VideoLAN for video (no worries about encrypted DVDs); Firefox, with Down Them All, FEBE, NoScript, Web Search Pro and Zotero as favourite add-ons; FileZilla for FTP-ing with my webhost; Grip for ripping CDs; KoverArtist for making CD covers; K3b for burning CDs & DVDs and for making audio CDs from MP3 or OGG files; Kooka for simple scanning (XSane gives you full control on all details; XScanImage keeps the middle, but seems a bit dodgy); XnView as a basic graphic tool; Krita for bitmap image editing; Inkscape for editing vector graphics; digiKam to manage the pictures from my camera (much easier than Canon's own MS software); ClamAV as virus tool, with freshclam for automatic updates; Kooldock, a simple but nice Mac OS X dock clone; Superkaramba to cheer up my desktop; KeyTouch to operate my Cherry multimedia desktop; Kpilot to synchronise my palmOne Treo with Kontact; Krusader for file management, although it still doesn't come too close to Total Commander; Grsync (a frontend for rsync) for backing up & synchronising; KControl and YaST for sysadmin tasks; RSIBreak to make me pause every 10 minutes and avoid RSI; Wine to run BibleWorks and my VanDale dictionaries; PySolFC as the only game I play; KStars to learn about astronomy (OK, WinStars 2 is more sophisticated); Kalzium to do the basics of chemistry; KBiff to notify me of new email, KNemo to monitor the network, KGet for quick downloads, Klipper for clipboard tricks, and… If I would like to chat, do VoIP, or use P2P -- which I don't -- there are many apps to choose from, and also gaming has much more on offer than my simple solitaire. You will have grasped that KDE is my desktop manager. Until version 4 has matured far enough I'll stick to version 3.5. I did try GNOME a short while, but, well, Linus said he'd go for KDE, you know -- although he himself will probably still work from a console most of the time. Anyway, KDE is more to my taste than GNOME. And the funny thing is that I did not even mention the tools that are most vital for running my system smoothly and stable. That is simply because I never need to look after them. They run in the background and automagically deal with vital issues such as networking, firewall, encryption, journaling, mounting/unmounting, multitasking, sound system, window management and so on. So, why don't YOU have a lot of fun today? Back to top |
| The Prophetic Voice of Linux First published 23/11/2008
Updated 26/12/2008 I have already explained why I like Linux. All I've said there is true, but actually there is more. Apart from all the practical and rational arguments there is something behind the Linux concept that I think is the strongest reason to prefer it as an operating system and a development platform. Ethos and pathos As the iconic example of open source software (OSS) Linux fits much better in the postmodern culture we are all part of than the Windows-based proprietary products which have monopolised the IT world, and are totally focussed on controlling the user and the market. Bill Gates clearly shows this in his book Business @ The Speed Of Thought: his digital nervous system is strictly hierarchical. As Eric S. Raymond explained, this traditional, still dominating, way of producing and using software is like building a cathedral, a huge, centrally directed project. But today's world is rapidly moving away from that and has become a global bazaar where everyone can contribute and exchange. To some extent my argument will be ethical, but moreover it will explore the principles on which Linux is based. Do not worry. I am not going to give a long rant about good and bad software manufacturers, nor will this be a piece of monomaniac OSS evangelism. Others can do that better than me. More than the ethos of OSS, it is its pathos that interests me. The ethos is about what you want and the choices you make. That's important of course, but it can waver in opportunistic ways, or simply be neglected. The pathos is about what you intuitively know to be the right thing, down in your guts. It is the prophetic voice revealing what is major and minor, which way to go or not to go, what brings in truth and what belies us. You can try to walk away from the pathos, but if you are honest, you cannot. Aha. Is it even worse than evangelism? Well, surely I don't hope so. I know, it is not very Anglo-Saxon to talk about Principles, but sometimes it just helps. I also know that Linus himself is probably one of the least philosophical people when it comes down to the Meaning of Linux, but that does not rule out that others can approach it a bit more contemplatively. After all, there is more in heaven and earth than our philosophy can dream of. Download the whole essay (PDF, 283 KB). Back to top |
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