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LINUX VOICE STAR LETTER FIND OF THE FORTNIGHT Thanks for the pointer to looks good on the 10.1–inch Tanglu [DistroHopper, LV008]. LED 1024x600 display. Even from the live DVD Installation to my netbook the KDE version was more completed in about 30 responsive than I would minutes. Tanglu detected expect on my Gateway the netbook platform then LT4004u with Intel Atom configured the desktop for the N2600 CPU and 3600 KDE 4 netbook GUI. Graphics Media Accelerator System Monitor showed (GMA). It just booted and got four threads consuming less down to business without than 20% of CPU capacity, needing any intervention from indicating that Tanglu me. Other flavours of OS have installed the Intel drivers for been troublesome with this the GMA: SolydK failed in this combination of CPU, GMA and area, resorted to software Broadcom network interface. rendering of the graphics, Debian, but with with graphical polish and a regular release cycle… In the past, I have found producing a single-thread CPU sounds familiar… sounds like Ubuntu! KDE to be ponderously load of around 70% capacity – baroque despite being well- SolydK took over two hours to Ben says: I’m glad you like it! made that it’s refreshing to developed. The newer version install too We see so many Debian/Ubuntu see a distro trying something of KDE delivered with Tanglu Andrew Shead respins with minimal changes authentically new.

WE FAIL A couple of points. Your Arduino The use of Processing is entirely tutorial [in LV011] contained an optional: for standalone projects error. The Arduino does not run the where the Arduino is to run Processing language, although it’s autonomously there is no choice a commonly held misconception other than to use a sketch written that it does. In fact “sketches” are in C/++. written in C or C++ as is evident Secondly I notice you regularly if you examine the code in the advocate DOSBox rather than article. Processing is a language DOSEMU for running DOS that runs on another computer programs. The last time I looked at and communicates using a serial this – admittedly some years ago Wire stuff up, then protocol with an Arduino running a – it was evident that DOSBox was now offers this capability, but it write code to make cool standard firmware “sketch” called designed for games, reducing the didn’t when I tried it. It struck me things happen – that’s Firmata. The following link makes effective CPU speed accordingly. as a case of horses for courses. the simple genius this clear: DOSEMU runs DOS programs fast It’s a great magazine and I’ve behind the Arduino. http://playground.arduino.cc/ and is a program I use daily. Of just renewed my subscription! Interfacing/Processing course it’s possible that DOSBox Peter Hinch

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DRINKING Congratulations on hitting the one year mark! I have gladly renewed my subscription. Any thoughts on allowing subscribers to set up an auto-renewing subscription? I have that set up with your former publication, and it is a very nice convenience. And, great mugs! Yes, you all do look great in your photographs, but that’s not what I’m talking about. I’m talking about the coffee/tea mug (do you even drink tea from a mug?). After having my letter featured in LV002, I had to have one. It looks better in person than it does on your website. I was a bit apprehensive about having a piece of ceramic shipped from overseas, but your shipping department did a fantastic job on the packaging. The form fitting styrofoam container took the trip over the pond in grand style, showing a bit of wear and tear, but protecting its precious cargo without fail. The ability to publish an outstanding magazine AND ship mugs unbroken internationally? What other skills are you hiding? Paul Olson, Oklahoma, USA Americans! Thanks to should have got it running for new one at a time). On the mug question: Graham’s packing skills, Andrew says: Thanks! We’re all subscriptions as well. At first we could I drink tea from a 50-year-old pint your mug will reach the amazed by how quickly the year only take payments via PayPal, but mug that Mike brought me back from shores of liberty whole has gone by. It’s funny you should we’re incrementally improving things Germany. Hidden talents: Graham and unbroken – mention this: we do have Direct Debit (incrementally because if anything plays the piano. Mike can juggle. http://shop.linuxvoice. payments enabled for renewals now, went wrong it would be up to Ben to Ben was Worcestershire under-10s com/product/- and by the time you read this we fix it, so we’re only adding options freestyle wrestling champion. voice-mug.

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TUTORIAL DÉJÀ DUP DÉJÀ DUP TUTORIAL DÉJ What to back up? À DUP: Do you really need t BA o backup your entire home dir CKUP FOR ector y, or is Then there are apps that create their own directories to just an overkill? Here’s what you need to know while selecting store files. Most prompt you for the location, while some may TUTORIAL directories for backup. Most modern distros keep the files DISTRO HOPPER create them on their own during installation. Make sure you you’ve created or downloaded under direct EVERYONE ories such as check for and include such directories which are usually listed ~/Documents , ~/Downloads, and ~/Desktop, so you’ll want to under the Preferences section of the apps. Be vigilant, though. include them in your backups. Also don ’t forget to check Some of these directories contain cache directories, which /home for any important documents. Some apps, such as Get acquainted with the easiest backup t needlessly add to the backup’s size. Finally, if there’s a piece MAYANK SHARMA ool on the planet to help email clients, also keep your downloaded emails, attachments of software that’s crucial to you and you don’t want to spend you save yourself from the ine and address books under hidden dir vitable data apocalypse. ectories beneath your time downloading it again, back it up by saving the cache home folder, so mak sure you include them as well. directory for your distro’s package management system. As you might expect when one e care about you. No, we really do. Which is WHY DO THIS? why you should believe us when we say Next, move on to Storage location • You’d really risk losing that sooner or later you will lose valuable and use the Drop- Once the backup has been created, the Overview W down lis data? t to pick one of the supporte data. You can spend a fortune on a storage medium d locations. This window will inform you when the last backup was • Quick to set up and easy can be a local hard disk, a remo that’s anti-scratch, dust-resistant, heat-proof and te location that you taken and when the next one is scheduled. to use. connect to via FTP o contains no moving parts, but what yo r SSH, or a cloud storage service distro hops, backing up one’s data be that my own script isn’t the • Designed for the u really need to do is like Amazon’s S3. Depending on the storage location everyday desktop user. to invest some effort in backing up your data. Déjà Vu you select, the app will ask you for furth Although it isn’t particularly time consuming, er details. For To restore files from the backup, launch the app and example, if you select the FTP option, yo backing up data requires careful thought and u’ll be asked click on the Restore button in the Overview section. to provide the IP address of the FTP serve preparation, and involves more than just zipping r along with The app will launch the Restore wizard, which will first the authentication i files into a tarball. Unfortunately this nformation and the location of prompt you for the location of t is important. But I had an issue most efficient at backing up but means it’s often Although it’s changed somewhat, the main inter he backed up files. face of folder where you want to store th neglected. This is where Déjà Dup comes into play. e backups. To save Just like before, select the remote location wh the app still essentially contains only two buttons – t ere It’s diff o the backups to Amazon’s S3 it’ll need your S3 Access y erent from the plethora of other tools in that back up and restore data. ou’ve backed up the files and enter any associated Key ID and for the Rackspace Cloud F it has a minimal interface so as to not overwhelm iles service it’ll information such as the IP address and your login new users. But it need your username. credentials ’s based on the powerful Duplicity Déjà Dup gives you the flexibil . ity to include a large Finally, you can switch command line backup tool and provides ju to the Scheduling section Déjà Dup will then scan the remote when using Déjà Dup [featured I know I can restore my stuff. I st the right directory – for instance /home – in your backup, while location and number of featur and select a policy for keeping old backups. By default, in the next s es for desktop users who aren’t used specifying parts to leave out, ection it’ll display a time-stamped list of such as .cache/. old backups will be kept to the ways of a backup tool. On some di until the target storage all the backups. Select the one you w stros, such To help you get started this section already lists the ish to restore as Ubuntu, Dé location runs out of space, but you can also specify from an jà Dup ships pre-installed, while it’s Trash and Downloads fol d move on to the next step. The app will now ders, though many users a different time perio available in the official repos of most o d depending on the importance give you the option to either resto thers. You can might want to remove the latter from the list unless re the backed up of the data. Before you can set a schedule for th configure the software in a matter of minutes without you rea e files to their original location or into a specified folder. in our tutorial section, LV011], sometimes wonder when apps are lly don’t want to safeguard the contents of the ba delvin ckup you’ll have to activate the app by toggling the B g into lengthy documentation. Downloads folder. efore restoring the files, the app will prompt you for button at the top right-corner of the wi ndow to On. the password if the backed up files were password Date with data Once the configured backup is enabled, you can use protected. the pull-down list on the Scheduling se The first time you fire up the tool, it lands on the Prepare for a backup ction to either One of the best features of the app is its ability to run this backup every day or every week Overview page which, as expected, tells you that there , which is the restore individuals file as well. To do this, head to the after I tried to restore my data. recommended whether the person default opti While Déjà Dup takes the pain out of setting up the actual on. are no recent backups nor are there any scheduled. folder from which you have accidentally lost files. data backup process, a crucial part of the process is To create the initial backup, switch t Before it can save you from data doomsday, you’ll first o the Overview Right-click inside the folder and select the Restore preparing for it which involves careful consideration. For section and click o have to set it up. n the Back Up Now button. The tool Missing Files option from the c starters, you need to decide where you want to store your ontext-menu. The app Nav will provides a summary list of the directories involved w igate to the Folders To Save section, which by data. Keeping it on another partition of the same disk isn’t ill scan the folder against the most recent backup and will begin. While creating the backu default lists your Home directory. This is generally advisable, since the whole disk might fail and render the p, the app will of this folder and display a list of files that are in the Whilst I can’t fully remember the recommending them have actually backup cop ask you to optionally y useless. encrypt the backup. Y a safe bet for most users. If you know what you are ou can backup but currently missing from the folder. Now use One solution is to keep the backup on another disk. If enter a password in the space provided or doing you can also remove this location and add any choose the checkbox besides the listed files to select the ones you have multiple disks and a spare computer you can even to back up particular directories that yo the files without a password. This initial that you wish to restore u wish to back up. You set up your own Network Attached Storage device using and the app will restore their can backup may take some time, but subsequent backups also use the + button to add other folders on other software like Open Media Vault (instructions in our tutorial latest versions. are much faster because they are increm mounted drives or network shares. in LV009). To protect your data against physical disasters, ental and It’s worth noting that Déjà Dup is missing some of sequence of events now, I think used them enough to hit such such as fires, floods and theft, mak only back up data that has cha nged. Then switch to Folders To Ignore and specify e sure you keep the the flexibility you’d get with other backup tools. One backup as far away from the original as possible, perhaps folders you don’t need to back up. By separat such missing feature is the ability to crea ing on a cheap cloud storage service. Each method has its te backup the directories to include and ex sets to backup different file clude in the backup, advantages – hard disks are cheap and readily available s into different locations. while removable disks offer portability, and online storage Déjà Dup, instead, is designed to back up the specified is globally accessible. The kind of data you wish to back up folders into the specified destination, each and every my problem of NOT being able problems. also influences the choice of storage medium. A D VD might time you schedule it to run. Déjà Dup isn’t meant for be useful for holiday snapshots, but isn’t going to be much use in a complex environment like an enterpris use to a professional photographer. e, but is perfect for safeg You’ll also need to work out the appropriate backup uarding data for home and SOHO Use the Custom Location methodology. Do you want to back up manually or users and also gives you the flexibility to restore option to specify a remote automatically based on a schedule? The correct backup individual files from the backups with ease. to restore my data was linked to G White frequency varies based on the kind and value of data being location supported by the safeguarded. Depending on the siz Gnome Virtual File System e of the files, it might not Despite being a simple app, Déjà Dup offers advanced be a good idea to back them up completely everyda (GVFS). y either. features like incremental backups and stores multiple Mayank Sharma has been tinkering with Linux since the 90s time-stamped versions of backups. and contributes to a variety of techie publications.

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LV011 076 Tutorial Deja Dup.indd 76 host name or a change in which Andrew says: I’m pretty sure Mayank, LV011 076 Tutorial Deja Dup.indd 77 DNS service I used. Anyway, a host who wrote the Déjà Dup tutorial last Déjà Dup is an easy name change was my problem issue, has been using it for a while profound note, I take my hat off way to perform regular and since Déjà Dup didn’t allow now, and his two-page tutorial was to you for writing your own script! backups – if you aren’t me to specify the host name or more than enough to get new users Hackability – that’s the key. When backing up already, try even indicate which host name introduced to it (rather than being the existing solutions don’t work for it out. it was using I decided to write an exhaustive look at corner cases – whatever reason, free software gives my own Bash script and using but in this case your best bet would us the ability to make our own – that’s rsync do my own backup! It may be your distro’s forums). On a more why we like it so much. I’M HISTORY! I have been picking up your magazine since I saw a copy of issue 3 on one of my irregular visits to WHS. I like the mix of articles and tutorials. With my advancing years I look at the coverage you give to older systems and there, on page 99 of issue 10 was the computer room at the Atlas Computer Lab where I worked showing Doug House, Tony Sargent and, I think, Ros Haliwell on the tape decks. I actually missed working on the Atlas as it shut down before I joined the lab in 1976 as a ICL shift To have worked on engineer on the 1906a mainframe. I was also at the Lab, latterly all this in a college five miles a piece of the UK’s The Atlas Processor was still there, renamed “Rutherford Atlas Lab” from the Sony factory making the computing history such but was being de-commissioned. when a Cray 1 was shipped in, Raspberry Pi. It makes you weep as Atlas must be a great An urban myth at the time was for temporary storage for the sometimes. privilege. that on one occasion some circuit UK Meteorological Office at Gordon Ireson, South Wales boards were removed, allegedly for Bracknell. A very impressive piece an Atlas still working “Somewhere of hardware, complete with Freon Graham Says: Wow! Thanks for Underground”. cooling system. sharing that with us! We’re incredibly My Atlas claim to fame is that My wife has a history even older lucky that the history of our field is in 1978 I was asked by the ICL as she was a systems analyst so accessible – even if you start with engineer in charge, Ted Everson, working on LEO computers in the single-application analogue machines to build a 12-volt power supply so 1960s. with valves rather than programmable that the Atlas console could be on After 37 years as an engineer, I digital computers, computer science display at the building Reception am now back at college studying is still young enough that most of us Desk with some lights on, so I HND computer science, not a sniff can comprehend the timeline without was pleased to see in your article of Linux, all Microsoft, Adobe, having to bend our heads too much. that the console has been “re- Access, C#, Visual Basic and And don’t worry about the HND – the discovered and is back on display”. Oracle, just a tiny hint of MySQL, world will catch up with Linux one day.

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