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Speaking UNIX: The best-kept secrets of UNIX power users

Speaking UNIX: The best-kept secrets of UNIX power users
If you're wondering why I'm wearing dark sunglasses, a fake moustache, and a baseball cap (featuring the logo of professional curling team, The Floating Stones), I'm on the lam. I'm dodging black remote-controlled helicopters, pasty-white systems administrators, and the combined forces of many daemons to bring you some of the best-kept secrets of UNIX® power users. Don your aluminum foil hat and read on. Save the environment variables Most UNIX users amass settings in shell startup files, such as .bashrc (for the Bash shell) and .zshrc (for the Z shell), to recreate a preferred shell environment time and again. Like the shell, you can customize many other UNIX applications through environment variables. For example, the pager utility less defines a number of useful environment variables: The environment variable LESS stores command-line options, reducing what you type each time you invoke the pager. Back to top Dotting the landscape At the other extreme, consider fetchmail. !!

Learn Linux, 101: Manage file permissions and ownership Overview In this article, learn to control file access through correct use of file and directory permissions and ownerships. Learn to: Manage access permissions on both regular and special files as well as directoriesMaintain security using access modes such as suid, sgid, and the sticky bitChange the file creation maskGrant file access to group members Unless otherwise noted, the examples in this article use Fedora 13 with a 2.6.34 kernel. This article helps you prepare for Objective 104.5 in Topic 104 of the Linux Professional Institute's Junior Level Administration (LPIC-1) exam 101. We introduced some of the file and group ownership concepts of this article in our previous article "Learn Linux 101: Manage disk quotas." Prerequisites To get the most from the articles in this series, you should have a basic knowledge of Linux and a working Linux system on which you can practice the commands covered in this article. Back to top User and groups Who am I? Listing 1. What groups am I in?

How to Get Your AMD Graphics, Sound & Other Drivers to Work in Linux on Your Laptop How to Get Your AMD Graphics, Sound & Other Drivers to Work in Linux on Your Laptop With the purchase of my latest computer, installing Linux turned into a nightmare from Hell. The graphics drivers are probably the biggest issue that anyone with a newer computer will run into when installing Linux. AMD and NVIDIA are the dominant ones on the market, both of which have awful support. Not only do graphics give us trouble, but anyone with a switchable power laptop (when you can use just AC without battery, with the battery plugged in), HDMI, audio in and out, or anyone with any kind of wonky hardware will be likely scared off from the computer and from Linux until the end of time. From first hand experience, and a fiery, passionate love for Linux, I almost found myself running scared until I hacked together these lovely fixes that we will be going over today. Let's look at the issues that we will encounter, depending on which graphics driver the system is using. Audio Alsa does not work Video

Murtola: Systematic Coarse-Graining Using Structural Information: Applications to Lipid Membranes, ISBN 978-951-22-9855-6 Dissertation for the degree of Doctor of Science in Technology to be presented with due permission of the Faculty of Information and Natural Sciences for public examination and debate in Auditorium E at Helsinki University of Technology (Espoo, Finland) on the 16th of May, 2009, at 13 o'clock. Overview in PDF format (ISBN 978-951-22-9855-6) [5313 KB] Dissertation is also available in print (ISBN 978-951-22-9854-9) Abstract Within last 20 years, advances in computational power and methodology have made computer simulations an integral part of studies of biomolecular systems. Simulations on all-atom level are routinely used to study, e.g., microscopic details of lipid aggregates and proteins. However, many phenomena are still outside the reach of all-atom simulations, and coarser models are needed. The main part of this dissertation employs inverse Monte Carlo (IMC) for constructing CG models for a lipid membrane containing dipalmitoylphosphatidylcholine (DPPC) and cholesterol.

Learn Linux, 101: Manage shared libraries Overview In this article, learn to find and load the shared libraries that your Linux programs need. Learn to: Determine which libraries a program needsKnow how the system finds shared librariesLoad shared libraries This article helps you prepare for Objective 102.3 in Topic 102 of the Linux Professional Institute's Junior Level Administration (LPIC-1) exam 101. Prerequisites To get the most from the articles in this series, you should have a basic knowledge of Linux and a working Linux system on which you can practice the commands covered in this article. Back to top Static and dynamic linking Linux systems have two types of executable programs: Statically linked executables contain all the library functions that they need to execute; all library functions are linked into the executable. An interesting example on many Linux systems is the ln command (/bin/ln), which creates links between files, either hard links or soft (or symbolic) links. Listing 1. Which libraries are needed? Listing 2.

Bash scripting for beginning system administrators A UNIX shell is essentially the API between the user, the kernel, and the system hardware. The shell is very important on any UNIX or Linux system and is one of the most vital aspects to learn proper systems administration and security. Typically driven by a CLI, the shell can literally make or break your system. The open source bash shell that this article examines is one of the most powerful, practical, and extensible shells available. In this article, you will learn the basic techniques of bash scripting, its everyday uses, and methods for employing it to create near-bulletproof shell scripts. History of the bash shell The Bourne Again Shell (bash) got its start in 1987, when it was written as a GNU project that many Linux distributions quickly adopted. One of the more positive aspects of bash is its built-in security features. Bash command syntax and keywords have taken and improved upon the architecture and technical details of the Korn shell (ksh) and the C shell (csh). Back to top

How Do I Get Cool Desktop Effects in Linux? Compiz has spoiled me. It's not at all uncommon for me to have easily in excess of 100 windows open. Favorite plugins? Oh boy, oh boy, oh boy! Scale plugin. (Don't forget the Scale Window Title Filter) When windows are scaled, start typing, enjoy. Put. Window Rules and Place Windows. Window Decorations I like eliminating the decorations (titlebar/borders) for various types of windows. Window Previews Yup. Trailfocus This plugin adjusts the opacity, brightness, and saturation of windows based upon how recently they've been focused. Opacity, Brightness, and Saturation Allows you to bind keypresses to adjustments in the settings for a particular window. Enhanced Zoom Desktop An absolute must when viewing Flash on Linux. Snapping windows Allows you to set the affinity the window borders have for other windows and the edges of the screen. Window Cube Sure, it's eye-candyish, but the subtle visual/spatial cues it provides are actually useful. Wobbly Windows, Paint Fire, etc.

Administration de machines Unix dans plusieurs fuseaux horaires Première rédaction de cet article le 16 décembre 2011Dernière mise à jour le 17 décembre 2011 Si vous administrez des machines Unix situées dans plusieurs fuseaux horaires, vous vous êtes peut-être déjà posé la question : quel fuseau indiquer à la machine ? Celui de sa localisation physique ? Mais n'est-ce pas pénible que la commande date donne cette heure UTC qui ne correspond pas au vécu de l'humain ? % date Fri Dec 16 20:03:03 UTC 2011 % export TZ=Europe/Paris % % date Fri Dec 16 21:03:08 CET 2011 Même chose pour ls. Évidemmment, aucune solution n'est parfaite. % TZ=Africa/Douala date --date="2011-12-16 12:00:00Z" Fri Dec 16 13:00:00 WAT 2011 (Le format utilisé est celui du RFC 3339, Z signifiant UTC.) Si on veut faire l'inverse, trouver quelle sera l'heure UTC correspondant à une certaine heure légale (ici, on se demande quelle sera l'heure UTC lorsqu'il est cinq heures du matin en Californie) : Une dernière chose sur les fuseaux horaires. mais les utilisateurs n'y pensent pas toujours.

Learn Linux, 101: Runlevels, shutdown, and reboot Overview In this article, learn to shut down or reboot your Linux system, warn users that the system is going down, and switch to single-user mode or a more or less restrictive runlevel. Learn to: Set the default runlevelChange between runlevelsChange to single-user modeShut down or reboot the system from the command lineAlert users about major system events, including switching to another runlevelTerminate processes properly Unless otherwise noted, the examples in this article use a Fedora 8 system with a 2.6.26 kernel. This article helps you prepare for Objective 101.3 in Topic 101 of the Linux Professional Institute's Junior Level Administration (LPIC-1) exam 101. Note: This article includes material for the LPI Exam 101: Objective Changes as of July 2, 2012. Prerequisites To get the most from the articles in this series, you should have a basic knowledge of Linux and a working Linux system on which to practice the commands covered in this article. Back to top Runlevels Table 1. Table 2.

Plasma/HowTo/4.5 - KDE UserBase The Plasma Workspace is one of the key technologies of KDE SC 4.x (also known as the "Pillars of KDE"), and one of the most visible to users. As Plasma Desktop treats the user interface differently than a traditional desktop, there may be confusion as to what the Plasma Desktop is, what it does, and how to perform common tasks. The purpose of this document is to show how to perform common tasks in Plasma Desktop. Each HowTo consists of one topic and a short animation, which is reached by clicking on the link. The animations are encoded in the GIF format and can thus be viewed in most modern web browsers without any additional plugins installed. Note that the animations are looped. HowTo Widgets Desktop Widgets Add widget to desktop Panel Widgets Add widget to panel Icons Desktop Panel Extenders Activities Further information For reuse To link to an animation from another UserBase article, a thumbnail can be posted. The code to do that is The animations can also be used outside of UserBase.

Learn Linux, 101: The Linux command line Overview This article gives you a brief introduction to some of the major features of the bash shell, and covers the following topics: Interacting with shells and commands using the command lineUsing valid commands and command sequencesDefining, modifying, referencing, and exporting environment variablesAccessing command history and editing facilitiesInvoking commands in the path and outside the pathUsing man (manual) pages to find out about commands This article helps you prepare for Objective 103.1 in Topic 103 of the Junior Level Administration (LPIC-1) exam 101. Back to top The bash shell The bash shell is one of several shells available for Linux. Before we delve deeper into bash, recall that a shell is a program that accepts and executes commands. Shells have some builtin commands, such as cd, break, and exec. Shells also use three standard I/O streams: Input streams provide input to programs, usually from terminal keystrokes. Listing 1. [db2inst1@echidna db2inst1]$ ian@lyrebird:~> $

How To Boot An ISO With GRUB2 (The Easy Way!) If you want to try out a new Linux distro, be it the latest Ubuntu 11.04 Natty Narwhal daily ISO or any other (I've only tested it with Ubuntu though!) and don't want to burn a CD each time you want to try a new daily build (and you don't have an USB memory stick around), you can use a cool GRUB 2 feature that lets you boot a live CD ISO directly from your hard disk. You can also use this method to boot varous utilities such as Super Grub Disk, SystemRescueCD, Parted Magic and so on. Usually, setting up GRUB 2 to boot an ISO can be quite a difficult process (well, not that difficult but for some reason it always failed for me) but you can do this with just a few clicks thanks to Unetbootin. I've recorded a video showing the Unetbootin Grub2 menu entry and then booting the latest Ubuntu 11.04 daily ISO using this method, however the video is very bad in quality (my cam sucks) so I didn't embed it into this post, but you can watch it @ YouTube if you want. 1. 2.

Learn Linux, 101: Boot the system Overview This article will help you understand the boot sequence from BIOS to boot completion, and will show you how to: Give common commands to the boot loaderGive options to the kernel at boot time Check boot events in the log files Some aspects of the boot process are common to most systems, but some hardware-related aspects are specific to a particular architecture. Unless otherwise noted, the examples in this article generally use Fedora 14, with a 2.6.35 kernel. This article helps you prepare for Objective 101.2 in Topic 101 of the Linux Professional Institute's Junior Level Administration (LPIC-1) exam 101. Prerequisites To get the most from the articles in this series, you should have a basic knowledge of Linux and a working Linux system on which you can practice the commands covered in this article. You should also be familiar with the material in our article, "Learn Linux 101: Hard disk layout." Back to top Boot sequence This works fine for a system with a single operating system.

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