Introduction to Linux
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BSD – Alternativen Zu Linux
∗BSD { Alternativen zu Linux Karl Lockhoff March 19, 2015 Inhaltsverzeichnis I Woher kommt BSD? I Was ist BSD? I Was ist sind die Unterschiede zwischen FreeBSD, NetBSD und OpenBSD? I Warum soll ich *BSD statt Linux einsetzen? I Chuck Haley und Bill Joy entwickeln den vi in Berkeley I Bill Joy erstellt eine Sammlung von Tools, 1BSD I Unix Version 7 erscheint I 2BSD erscheint (Basis f¨urdie Weiterentwicklung PDP-11) I 3BSD erscheint (erstmalig mit einen eigenen Kernel) I 4BSD erscheint (enth¨altdas fast file system (ffs)) I Bill Joy wechselt zu Sun Microsystems I Kirk McKusick ¨ubernimmt die Entwicklung von BSD I 1978 I 1979 I 1980 I 1981 Woher kommt BSD? I 1976 I Unix Version 6 erscheint I 2BSD erscheint (Basis f¨urdie Weiterentwicklung PDP-11) I 3BSD erscheint (erstmalig mit einen eigenen Kernel) I 4BSD erscheint (enth¨altdas fast file system (ffs)) I Bill Joy wechselt zu Sun Microsystems I Kirk McKusick ¨ubernimmt die Entwicklung von BSD I Bill Joy erstellt eine Sammlung von Tools, 1BSD I Unix Version 7 erscheint I 1979 I 1980 I 1981 Woher kommt BSD? I 1976 I Unix Version 6 erscheint I 1978 I Chuck Haley und Bill Joy entwickeln den vi in Berkeley I 2BSD erscheint (Basis f¨urdie Weiterentwicklung PDP-11) I 3BSD erscheint (erstmalig mit einen eigenen Kernel) I 4BSD erscheint (enth¨altdas fast file system (ffs)) I Bill Joy wechselt zu Sun Microsystems I Kirk McKusick ¨ubernimmt die Entwicklung von BSD I Unix Version 7 erscheint I 1979 I 1980 I 1981 Woher kommt BSD? I 1976 I Unix Version 6 erscheint I 1978 I Chuck Haley und Bill Joy entwickeln den -
Beginning Portable Shell Scripting from Novice to Professional
Beginning Portable Shell Scripting From Novice to Professional Peter Seebach 10436fmfinal 1 10/23/08 10:40:24 PM Beginning Portable Shell Scripting: From Novice to Professional Copyright © 2008 by Peter Seebach All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher. ISBN-13 (pbk): 978-1-4302-1043-6 ISBN-10 (pbk): 1-4302-1043-5 ISBN-13 (electronic): 978-1-4302-1044-3 ISBN-10 (electronic): 1-4302-1044-3 Printed and bound in the United States of America 9 8 7 6 5 4 3 2 1 Trademarked names may appear in this book. Rather than use a trademark symbol with every occurrence of a trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. Lead Editor: Frank Pohlmann Technical Reviewer: Gary V. Vaughan Editorial Board: Clay Andres, Steve Anglin, Ewan Buckingham, Tony Campbell, Gary Cornell, Jonathan Gennick, Michelle Lowman, Matthew Moodie, Jeffrey Pepper, Frank Pohlmann, Ben Renow-Clarke, Dominic Shakeshaft, Matt Wade, Tom Welsh Project Manager: Richard Dal Porto Copy Editor: Kim Benbow Associate Production Director: Kari Brooks-Copony Production Editor: Katie Stence Compositor: Linda Weidemann, Wolf Creek Press Proofreader: Dan Shaw Indexer: Broccoli Information Management Cover Designer: Kurt Krames Manufacturing Director: Tom Debolski Distributed to the book trade worldwide by Springer-Verlag New York, Inc., 233 Spring Street, 6th Floor, New York, NY 10013. -
Logiciel Libre, Une Introduction Part I Perspective Historique Des Étapes
Logiciel libre, une introduction Logiciel libre, une introduction Logiciel libre, une introduction Part I Roberto Di Cosmo Perspective historique Université Paris Diderot UFR Informatique Laboratoire Preuves, Programmes et Systèmes [email protected] 7 Février 2012 Logiciel libre, une introduction Logiciel libre, une introduction Une brève histoire du logiciel Une brève histoire du logiciel Des étapes importantes Une brève histoire du logiciel I Années 50-60: Logiciel libre ante litteram Logiciel Libre aux origines La propriétarisation du logiciel I Années 70: La proprietarisation du logiciel I Années 70-80: Les briques de base I Donald Knuth et TEX Le logiciel libre ante litteram I X Windows System Le système TEX I AT&T et Unix Le système X I Années 80: le matériel devient suffisamment puissant pour des AT&T et Unix vrai OS Linux I Années 80: Richard Stallman, GNU et la Free Software Foundation Le logiciel libre formalisé I Années 1990: Linux, GNU/Linux etc.: la prise de conscience I Années 2000 : l’expansion Les années 1990 Logiciel libre, une introduction Logiciel libre, une introduction Une brève histoire du logiciel Une brève histoire du logiciel Logiciel Libre aux origines Logiciel Libre aux origines Au début le logiciel fût distribué librement. c’était une nécéssité Jusqu’à la fin des années 1960, le logiciel, avec les sources, était N’oublions pas les raisons techniques de cette réalité: distribué gratuitement, comme un complément pour les ordinateurs I modèle de service clé en main comprenant hw & sw & vendus (très chers) à l’époque. service I logiciel très dépendant de la machine utilisateur (n. -
A First Course to Openfoam
Basic Shell Scripting Slides from Wei Feinstein HPC User Services LSU HPC & LON [email protected] September 2018 Outline • Introduction to Linux Shell • Shell Scripting Basics • Variables/Special Characters • Arithmetic Operations • Arrays • Beyond Basic Shell Scripting – Flow Control – Functions • Advanced Text Processing Commands (grep, sed, awk) Basic Shell Scripting 2 Linux System Architecture Basic Shell Scripting 3 Linux Shell What is a Shell ▪ An application running on top of the kernel and provides a command line interface to the system ▪ Process user’s commands, gather input from user and execute programs ▪ Types of shell with varied features o sh o csh o ksh o bash o tcsh Basic Shell Scripting 4 Shell Comparison Software sh csh ksh bash tcsh Programming language y y y y y Shell variables y y y y y Command alias n y y y y Command history n y y y y Filename autocompletion n y* y* y y Command line editing n n y* y y Job control n y y y y *: not by default http://www.cis.rit.edu/class/simg211/unixintro/Shell.html Basic Shell Scripting 5 What can you do with a shell? ▪ Check the current shell ▪ echo $SHELL ▪ List available shells on the system ▪ cat /etc/shells ▪ Change to another shell ▪ csh ▪ Date ▪ date ▪ wget: get online files ▪ wget https://ftp.gnu.org/gnu/gcc/gcc-7.1.0/gcc-7.1.0.tar.gz ▪ Compile and run applications ▪ gcc hello.c –o hello ▪ ./hello ▪ What we need to learn today? o Automation of an entire script of commands! o Use the shell script to run jobs – Write job scripts Basic Shell Scripting 6 Shell Scripting ▪ Script: a program written for a software environment to automate execution of tasks ▪ A series of shell commands put together in a file ▪ When the script is executed, those commands will be executed one line at a time automatically ▪ Shell script is interpreted, not compiled. -
Linux Hardening Techniques Vasudev Baldwa Ubnetdef, Spring 2021 Agenda
Linux Hardening Techniques Vasudev Baldwa UBNetDef, Spring 2021 Agenda 1. What is Systems Hardening? 2. Basic Principles 3. Updates & Encryption 4. Monitoring 5. Services 6. Firewalls 7. Logging What is System Hardening? ⬡ A collection of tools, techniques, and best practices to reduce vulnerability in technology applications, systems, infrastructure, firmware, and other areas ⬡ 3 major areas: OS vs Software vs Network ⬠ When have we done hardening in this class before? ⬠ This lecture is focusing mostly on OS and software level Why Harden? ⬡ Firewalls can only get us so far, what happens when at attack is inside the network? ⬠ If you have nothing protecting your systems you are in trouble ⬡ We want some kind of secondary protection A Few Cybersecurity Principles ⬡ Zero Trust Security ⬠ Instead of assuming everything behind the firewall is safe, Zero Trust verifies each request as though it originates from an unsecure network ⬡ Principle of Least Privilege ⬠ Only privileges needed to complete a task should be allowed ⬠ Users should not have domain administrator/root privileges ⬡ Principle of Least Common Mechanism ⬠ Mechanisms used to access resources should not be shared in order to avoid the transmission of data. ⬠ Shared resources should not be used to access resources The Threat Model ⬡ A process by which potential threats can be identified and prioritized. ⬠ If you have a web server that feeds input to a mysql database, then protecting against mysql injections would be prioritized in your model. 2 considerations ⬡ *nix like is a very -
Processes and Job Control
Processes and Job Control Hour 17 PObjectives < Definitions: process, orphan, and zombie < System processes < Process creation < Examining processes: the ps command < Job control: &, nohup, fg, bg, jobs, ( ), and kill < Exit status Copyright © 1998-2002 Delroy A. Brinkerhoff. All Rights Reserved. Hour 17 Unix Slide 1 of 12 Process Also called a job by C and Korn shells PWhen a program or executable file is loaded from disk and started running (i.e., when a command is run), it is called a process vi pid 641 < identified by a unique process ID (PID) number < has an owner vi < private data vi PA program can be loaded more than once pid 895 < creates multiple processes vi < each process has a different PID < each process may have a different owner PPIDs are unique, nonnegative integers < numbers recycle without collisions Hour 17 Unix Slide 2 of 12 System Processes Processes created during system boot P0System kernel < “hand crafted” at boot < called swap in older versions (swaps the CPU between processes) < called sched in newer versions (schedules processes) < creates process 1 P1 init (the parent of all processes except process 0) < general process spawner < begins building locale-related environment < sets or changes the system run-level P2 page daemon (pageout on most systems) P3 file system flusher (fsflush) Hour 17 Unix Slide 3 of 12 Process Life Cycle Overview of creating new processes fork init init pid 467 Pfork creates two identical pid 1 exec processes (parent and child) getty pid 467 Pexec < replaces the process’s instructions -
BSD Projects IV – BSD Certification • Main Features • Community • Future Directions a (Very) Brief History of BSD
BSD Overview Jim Brown May 24, 2012 BSD Overview - 5/24/2012 - Jim Brown, ISD BSD Overview I – A Brief History of BSD III – Cool Hot Stuff • ATT UCB Partnership • Batteries Included • ATT(USL) Lawsuit • ZFS , Hammer • BSD Family Tree • pf Firewall, pfSense • BSD License • Capsicum • Virtualization Topics • Jails, Xen, etc. • Desktop PC-BSD II – The Core BSD Projects IV – BSD Certification • Main Features • Community • Future Directions A (Very) Brief History of BSD 1971 – ATT cheaply licenses Unix source code to many organizations, including UCB as educational material 1975 – Ken Thompson takes a sabbatical from ATT, brings the latest Unix source on tape to UCB his alma mater to run on a PDP 11 which UCB provided. (Industry/academic partnerships were much more common back then.) Computer Science students (notably Bill Joy and Chuck Haley) at UCB begin to make numerous improvements to Unix and make them available on tape as the “Berkeley Software Distribution” - BSD A (Very) Brief History of BSD Some notable CSRG • 1980 – Computer Science Research Group members (CSRG) forms at UCB with DARPA funding to make many more improvements to Unix - job control, autoreboot, fast filesystem, gigabit address space, Lisp, IPC, sockets, TCP/IP stack + applications, r* utils, machine independence, rewriting almost all ATT code with UCB/CSRG code, including many ports • 1991 – The Networking Release 2 tape is released on the Internet via anon FTP. A 386 port quickly follows by Bill and Lynne Jolitz. The NetBSD group is formed- the first Open Source community entirely on the Internet • 1992 – A commercial version, BSDI (sold for $995, 1-800-ITS-UNIX) draws the ire of USL/ATT. -
Multiresolution Recurrent Neural Networks: an Application to Dialogue Response Generation
Multiresolution Recurrent Neural Networks: An Application to Dialogue Response Generation Iulian Vlad Serban∗◦ Tim Klinger University of Montreal IBM Research 2920 chemin de la Tour, T. J. Watson Research Center, Montréal, QC, Canada Yorktown Heights, NY, USA Gerald Tesauro Kartik Talamadupula Bowen Zhou IBM Research IBM Research IBM Research T. J. Watson Research Center, T. J. Watson Research Center, T. J. Watson Research Center, Yorktown Heights, Yorktown Heights, Yorktown Heights, NY, USA NY, USA NY, USA Yoshua Bengioy◦ Aaron Courville◦ University of Montreal University of Montreal 2920 chemin de la Tour, 2920 chemin de la Tour, Montréal, QC, Canada Montréal, QC, Canada Abstract We introduce the multiresolution recurrent neural network, which extends the sequence-to-sequence framework to model natural language generation as two parallel discrete stochastic processes: a sequence of high-level coarse tokens, and a sequence of natural language tokens. There are many ways to estimate or learn the high-level coarse tokens, but we argue that a simple extraction procedure is sufficient to capture a wealth of high-level discourse semantics. Such procedure allows training the multiresolution recurrent neural network by maximizing the exact joint log-likelihood over both sequences. In contrast to the standard log- likelihood objective w.r.t. natural language tokens (word perplexity), optimizing the joint log-likelihood biases the model towards modeling high-level abstractions. We apply the proposed model to the task of dialogue response generation in arXiv:1606.00776v2 [cs.CL] 14 Jun 2016 two challenging domains: the Ubuntu technical support domain, and Twitter conversations. On Ubuntu, the model outperforms competing approaches by a substantial margin, achieving state-of-the-art results according to both automatic evaluation metrics and a human evaluation study. -
Linux on the Move
Guest Editors’ Introduction What is Linux? And why should you care? This focus section has insights for both newcomers and diehard fans. Linux on the Move Terry Bollinger, The Mitre Corporation Peter Beckman, Los Alamos National Laboratory inux is a free, open-source operating system that looks like Unix, L except that it runs on PCs as well as other platforms. Linux was created by Linus Torvalds in 1991. Today, Linux is cooperatively improved by Torvalds and thousands of volunteers from around the world using open-source development methods. At this point in time, “Linux” generally refers to the entire suite of software in a distribution, from the operating system kernel to the Web server and graphical user interface. When we say that Linux is “free” we mean, well…free. You do not need to pay money to get a copy of it, although it is usually more convenient to buy an inexpen- sive CD-ROM copy than download an entire distribution over the Internet. Once you get a copy of Linux, you also have the right to make as many copies of it as you want. 30 IEEE Software January/February 1999 0740-7459/99/$10.00 © 1999 . DEFINING TERMS GETTING RESULTS By “open source”we mean that you also have the The only traditional software practice that open- right to get copies of all the source code from which source software developers do follow is peer review, Linux and its associated tools were originally com- and they do that with a vengeance. Each piece of piled. There are no magical, mysterious binary files, source code is placed on display in front of a global although you can of course get the Linux system precompiled if you prefer. -
07 07 Unixintropart2 Lucio Week 3
Unix Basics Command line tools Daniel Lucio Overview • Where to use it? • Command syntax • What are commands? • Where to get help? • Standard streams(stdin, stdout, stderr) • Pipelines (Power of combining commands) • Redirection • More Information Introduction to Unix Where to use it? • Login to a Unix system like ’kraken’ or any other NICS/ UT/XSEDE resource. • Download and boot from a Linux LiveCD either from a CD/DVD or USB drive. • http://www.puppylinux.com/ • http://www.knopper.net/knoppix/index-en.html • http://www.ubuntu.com/ Introduction to Unix Where to use it? • Install Cygwin: a collection of tools which provide a Linux look and feel environment for Windows. • http://cygwin.com/index.html • https://newton.utk.edu/bin/view/Main/Workshop0InstallingCygwin • Online terminal emulator • http://bellard.org/jslinux/ • http://cb.vu/ • http://simpleshell.com/ Introduction to Unix Command syntax $ command [<options>] [<file> | <argument> ...] Example: cp [-R [-H | -L | -P]] [-fi | -n] [-apvX] source_file target_file Introduction to Unix What are commands? • An executable program (date) • A command built into the shell itself (cd) • A shell program/function • An alias Introduction to Unix Bash commands (Linux) alias! crontab! false! if! mknod! ram! strace! unshar! apropos! csplit! fdformat! ifconfig! more! rcp! su! until! apt-get! cut! fdisk! ifdown! mount! read! sudo! uptime! aptitude! date! fg! ifup! mtools! readarray! sum! useradd! aspell! dc! fgrep! import! mtr! readonly! suspend! userdel! awk! dd! file! install! mv! reboot! symlink! -
Ten Steps to Linux Survival
Ten Steps to Linux Survival Bash for Windows People Jim Lehmer 2015 Steps List of Figures 5 -1 Introduction 13 Batteries Not Included .............................. 14 Please, Give (Suggestions) Generously ...................... 15 Why? ........................................ 15 Caveat Administrator ............................... 17 Conventions .................................... 17 How to Get There from Here ........................... 19 Acknowledgments ................................. 20 0 Some History 21 Why Does This Matter? .............................. 23 Panic at the Distro ................................. 25 Get Embed With Me ................................ 26 Cygwin ....................................... 26 1 Come Out of Your Shell 29 bash Built-Ins .................................... 30 Everything You Know is (Almost) Wrong ..................... 32 You’re a Product of Your Environment (Variables) . 35 Who Am I? .................................. 36 Paths (a Part of Any Balanced Shrubbery) .................... 37 Open Your Shell and Interact ........................... 38 Getting Lazy .................................... 39 2 File Under ”Directories” 43 Looking at Files .................................. 44 A Brief Detour Around Parameters ........................ 46 More Poking at Files ............................... 47 Sorting Things Out ................................ 51 Rearranging Deck Chairs ............................. 55 Making Files Disappear .............................. 56 2 touch Me ..................................... -
Automating Admin Tasks Using Shell Scripts and Cron Vijay Kumar Adhikari
AutomatingAutomating adminadmin taskstasks usingusing shellshell scriptsscripts andand croncron VijayVijay KumarKumar AdhikariAdhikari vijayvijay@@kcmkcm..eduedu..npnp HowHow dodo wewe go?go? IntroductionIntroduction toto shellshell scriptsscripts ExampleExample scriptsscripts IntroduceIntroduce conceptsconcepts atat wewe encounterencounter themthem inin examplesexamples IntroductionIntroduction toto croncron tooltool ExamplesExamples ShellShell The “Shell” is a program which provides a basic human-OS interface. Two main ‘flavors’ of Shells: – sh, or bourne shell. It’s derivatives include ksh (korn shell) and now, the most widely used, bash (bourne again shell). – csh or C-shell. Widely used form is the very popular tcsh. – We will be talking about bash today. shsh scriptscript syntaxsyntax The first line of a sh script must (should?) start as follows: #!/bin/sh (shebang, http://en.wikipedia.org/wiki/Shebang ) Simple unix commands and other structures follow. Any unquoted # is treated as the beginning of a comment until end-of-line Environment variables are $EXPANDED “Back-tick” subshells are executed and `expanded` HelloHello WorldWorld scriptscript #!/bin/bash #Prints “Hello World” and exists echo “Hello World” echo “$USER, your current directory is $PWD” echo `ls` exit #Clean way to exit a shell script ---------------------------------------- To run i. sh hello.sh ii. chmod +x hello.sh ./hello.sh VariablesVariables MESSAGE="Hello World“ #no $ SHORT_MESSAGE=hi NUMBER=1 PI=3.142 OTHER_PI="3.142“ MIXED=123abc new_var=$PI echo $OTHER_PI # $ precedes when using the var Notice that there is no space before and after the ‘=‘. VariablesVariables contcont…… #!/bin/bash echo "What is your name?" read USER_NAME # Input from user echo "Hello $USER_NAME" echo "I will create you a file called ${USER_NAME}_file" touch "${USER_NAME}_file" -------------------------------------- Exercise: Write a script that upon invocation shows the time and date and lists all logged-in users.