Linux Directory Structure (File System Structure) Explained with Examples by Ramesh Natarajan on September 8, 2010 Have you wondered why certain programs are located under /bin, or /sbin, or /usr/bin, or /usr/sbin? For example, less command is located under /usr/bin directory. Why not /bin, or /sbin, or /usr/sbin? In this article, let us review the Linux filesystem structures and understand the meaning of individual high-level directories. 1. / – Root Every single file and directory starts from the root directory.Only root user has write privilege under this directory.Please note that /root is root user’s home directory, which is not same as /. 2. Contains binary executables.Common linux commands you need to use in single-user modes are located under this directory.Commands used by all the users of the system are located here.For example: ps, ls, ping, grep, cp. 3. 4. Contains configuration files required by all programs.This also contains startup and shutdown shell scripts used to start/stop individual programs.For example: /etc/resolv.conf, /etc/logrotate.conf
Korn Shell (Bash) Le but▲ Le shell permet de réaliser des petits programmes qui deviennent des outils. Ces outils faciliteront les tâches répétitives de l'administrateur, de l'utilisateur. Pour le programmeur, un en-capsulage de ces sources et un enchaînement de programme peuvent être utiles. Le rôle▲ Le shell est : l'interpréteur de commande ; l'interface entre l'utilisateur et les commandes ; un langage de programmation (interpréteur), il permet donc de réaliser de nouvelles commandes ; un gestionnaire de processus ; un environnement de travail configurable. Les avantages du Korn Shell▲ Le Korn shell regroupe les fonctions du C shell et du Bourne shell, tout en apportant de nouvelles propriétés, afin d'obtenir un shell plus convivial, plus puissant et plus rapide. Le Korn shell a les possibilités supplémentaires suivantes : Les différences entre le Korn shell et le Bash sont suffisamment faibles pour envisager des scripts communs. Le choix du shell▲ Les choix possibles : La syntaxe▲ commande options arguments
Save Commands - GNU Emacs Manual 18.3.1 Commands for Saving Files These are the commands that relate to saving and writing files. C-x C-s Save the current buffer to its file (save-buffer). C-x s Save any or all buffers to their files (save-some-buffers). Forget that the current buffer has been changed (not-modified). C-x C-w Save the current buffer with a specified file name (write-file). M-x set-visited-file-name Change the file name under which the current buffer will be saved. When you wish to save the file and make your changes permanent, type C-x C-s (save-buffer). Wrote /u/rms/gnu/gnu.tasks If the current buffer is not modified (no changes have been made in it since the buffer was created or last saved), saving is not really done, because it would have no effect. (No changes need to be saved) With a prefix argument, C-u C-x C-s, Emacs also marks the buffer to be backed up when the next save is done. The command C-x s (save-some-buffers) offers to save any or all modified buffers. y n C-r d C-h reverting .
documentation The most useful software is sometimes rendered useless by poor or altogether missing documentation. Vim refuses to succumb to death by underdocumentation. With a book to extensive help files to a tips collection, all audiences should be pleased. Vim's online documentation system, accessible via the :help command, is an extensive cross-referenced and hyperlinked reference. It's kept up-to-date with the software and can answer almost any question about Vim's functionality. A new on-line version of the help can be found on appspot. For translations of the help files see the translation page. Steve Oualline wrote the first book completely dedicated to Vim. Especially useful for absolute beginners who fear being bored by learning the basic commands: Vim Adventure. Less playfull, but a bit faster to go through is the Vim tutor. A manual is great for reference, but voluminous reference materials aren't always the easiest way to locate answers to your questions. You can also watch videos.
Aprendiendo LaTeX Writing Your Own Toy OS (Part I) "Linux Gazette...making Linux just a little more fun!" By Krishnakumar R. This article is a hands-on tutorial for building a small boot sector. 1. 1.1 The Fancy Dress The microprocessor controls the computer. 1.2 Our Role Initially, control is in the hands of the BIOS. 1.3 The Plan First write a small program in 8086 assembly (don't be frightened; I will teach you how to write it), and copy it to the boot sector of the floppy. 2. as86 This is an assembler. ld86 This is the linker. gcc The C compiler. A free floppy A floppy will be used to store our operating system. Good Old Linux box You know what this is for. as86 and ld86 will be in most of the standard distributions. 3. 1, 2, 3, Start! 3.1 The Boot Sector Grab your favourite editor and type in these few lines. entry start start: mov ax,#0xb800 mov es,ax seg es mov [0],#0x41 seg es mov [1],#0x1f loop1: jmp loop1 This is an assembly language that as86 will understand. 0xb800 is the address of the video memory. mov ax,#0xb800 3.3 Let's Do It All .
Introduction à la programmation shell en Bash Interpréteur de commandes par défaut des systèmes GNU/Linux, bash est devenu pour les administrateurs système, un outil incontournable. Ce document présente les principales constructions syntaxiques de bash utilisées dans l'écriture des programmes shell (scripts shell). L'objectif premier a été de laisser de côté les redondances syntaxiques de ce langage de programmation, la subtilité des mécanismes de l'interpréteur, afin d'insister sur quelques concepts synthétiques tels que la substitution, la redirection ou le filtrage. Cet écrit étant destiné principalement aux étudiants de premier et deuxième cycle en informatique, j'ai choisi de le rédiger en adoptant un style 2Ex (1 Explication, 1 Exemple) qui devrait permettre au lecteur de mieux s'approprier chaque notion présentée. Cette publication étant loin d'être parfaite, j'encourage le lecteur à me faire parvenir ses remarques ou suggestions, ainsi qu'à me signaler toute inexactitude (e-mail).
Tutoriel Org (emacs org-mode) J'ai d'abord entré une titre de section appelé "Tasks" pour y placer les tâches. Ce n'est pas nécessaire mais c'est souvent pratique, surtout quand vous voulez garder la liste des tâches séparée du corps du document que vous écrivez. Les titres de sections de premier niveau commencent avec un astérisque; ceux des sections de deuxième niveau avec deux astérisque, et ainsi de suite. Dans org-mode, les entrées TODO sont toujours des titres de section. J'ai saisie une entrée TODO pour "Start new org file for tutorial." C'est un peu stupide, parce que nous avons déjà commencé un nouveau fichier. Voici le résultat : Remarquez comme org-mode utilise un marqueur temporel ("timestamp") pour enregistrer le moment où un élément TODO a été achevé. Ajoutons plus d'éléments TODO.
Vi Lovers Home Page "The Vi Lovers Home Page ... this makes a great starting point." (Learning the vi Editor, 6th Edition, O'Reilly, page 300) Contents IntroductionThe authorShould I use Vi? Introduction Vi (pronounce: "vee eye", not "six", not "vye") is an editor. Although other stories exist, the true one tells that Vi was originally written by Bill Joy in 1976. People got attached to Vi, and eventually it got included in System V. The Vi Lovers Home Page has links to the latest version of different Vi implementations. The author (of this page) My name is Thomer M. ]. I use Vim because I simply don't know of a better editor, but, admittedly, I haven't seriously tried anything else. Should I use Vi? Which editor to use is mainly a matter of taste, style, and needs. The long story is that, even though Vi is somewhat awkward to use at first, it enables fast, simple, and effective editing once you get the hang of it. Vi has its dark sides, too. There is no conclusion. Vi versions Unix, MS-DOS, Windows, and OS/2