Introduction to Bash Programming
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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. -
GNU Grep: Print Lines That Match Patterns Version 3.7, 8 August 2021
GNU Grep: Print lines that match patterns version 3.7, 8 August 2021 Alain Magloire et al. This manual is for grep, a pattern matching engine. Copyright c 1999{2002, 2005, 2008{2021 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled \GNU Free Documentation License". i Table of Contents 1 Introduction ::::::::::::::::::::::::::::::::::::: 1 2 Invoking grep :::::::::::::::::::::::::::::::::::: 2 2.1 Command-line Options ::::::::::::::::::::::::::::::::::::::::: 2 2.1.1 Generic Program Information :::::::::::::::::::::::::::::: 2 2.1.2 Matching Control :::::::::::::::::::::::::::::::::::::::::: 2 2.1.3 General Output Control ::::::::::::::::::::::::::::::::::: 3 2.1.4 Output Line Prefix Control :::::::::::::::::::::::::::::::: 5 2.1.5 Context Line Control :::::::::::::::::::::::::::::::::::::: 6 2.1.6 File and Directory Selection:::::::::::::::::::::::::::::::: 7 2.1.7 Other Options ::::::::::::::::::::::::::::::::::::::::::::: 9 2.2 Environment Variables:::::::::::::::::::::::::::::::::::::::::: 9 2.3 Exit Status :::::::::::::::::::::::::::::::::::::::::::::::::::: 12 2.4 grep Programs :::::::::::::::::::::::::::::::::::::::::::::::: 13 3 Regular Expressions ::::::::::::::::::::::::::: 14 3.1 Fundamental Structure :::::::::::::::::::::::::::::::::::::::: -
“Linux at the Command Line” Don Johnson of BU IS&T We’Ll Start with a Sign in Sheet
“Linux at the Command Line” Don Johnson of BU IS&T We’ll start with a sign in sheet. We’ll end with a class evaluation. We’ll cover as much as we can in the time allowed; if we don’t cover everything, you’ll pick it up as you continue working with Linux. This is a hands-on, lab class; ask questions at any time. Commands for you to type are in BOLD The Most Common O/S Used By BU Researchers When Working on a Server or Computer Cluster Linux is a Unix clone begun in 1991 and written from scratch by Linus Torvalds with assistance from a loosely-knit team of hackers across the Net. 64% of the world’s servers run some variant of Unix or Linux. The Android phone and the Kindle run Linux. a set of small Linux is an O/S core programs written by written by Linus Richard Stallman and Torvalds and others others. They are the AND GNU utilities. http://www.gnu.org/ Network: ssh, scp Shells: BASH, TCSH, clear, history, chsh, echo, set, setenv, xargs System Information: w, whoami, man, info, which, free, echo, date, cal, df, free Command Information: man, info Symbols: |, >, >>, <, ;, ~, ., .. Filters: grep, egrep, more, less, head, tail Hotkeys: <ctrl><c>, <ctrl><d> File System: ls, mkdir, cd, pwd, mv, touch, file, find, diff, cmp, du, chmod, find File Editors: gedit, nedit You need a “xterm” emulation – software that emulates an “X” terminal and that connects using the “SSH” Secure Shell protocol. ◦ Windows Use StarNet “X-Win32:” http://www.bu.edu/tech/support/desktop/ distribution/xwindows/xwin32/ ◦ Mac OS X “Terminal” is already installed Why? Darwin, the system on which Apple's Mac OS X is built, is a derivative of 4.4BSD-Lite2 and FreeBSD. -
Php Tutorial
PHP About the Tutorial The PHP Hypertext Preprocessor (PHP) is a programming language that allows web developers to create dynamic content that interacts with databases. PHP is basically used for developing web-based software applications. This tutorial will help you understand the basics of PHP and how to put it in practice. Audience This tutorial has been designed to meet the requirements of all those readers who are keen to learn the basics of PHP. Prerequisites Before proceeding with this tutorial, you should have a basic understanding of computer programming, Internet, Database, and MySQL. Copyright & Disclaimer © Copyright 2016 by Tutorials Point (I) Pvt. Ltd. All the content and graphics published in this e-book are the property of Tutorials Point (I) Pvt. Ltd. The user of this e-book is prohibited to reuse, retain, copy, distribute or republish any contents or a part of contents of this e-book in any manner without written consent of the publisher. We strive to update the contents of our website and tutorials as timely and as precisely as possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt. Ltd. provides no guarantee regarding the accuracy, timeliness or completeness of our website or its contents including this tutorial. If you discover any errors on our website or in this tutorial, please notify us at [email protected] i PHP Table of Contents About the Tutorial ........................................................................................................................................... -
Bash Guide for Beginners
Bash Guide for Beginners Machtelt Garrels Garrels BVBA <tille wants no spam _at_ garrels dot be> Version 1.11 Last updated 20081227 Edition Bash Guide for Beginners Table of Contents Introduction.........................................................................................................................................................1 1. Why this guide?...................................................................................................................................1 2. Who should read this book?.................................................................................................................1 3. New versions, translations and availability.........................................................................................2 4. Revision History..................................................................................................................................2 5. Contributions.......................................................................................................................................3 6. Feedback..............................................................................................................................................3 7. Copyright information.........................................................................................................................3 8. What do you need?...............................................................................................................................4 9. Conventions used in this -
A Common Framework for Scripting Tutorials Erik Hjelmås and Ivar
A Common Framework for Scripting Tutorials Erik Hjelmås and Ivar Farup Abstract A scripting tutorial should focus on teaching the characteristics of scripting languages, avoiding the pitfall of teaching only syntax conversion from system programming languages. Examples should be selected to emphasize features of scripting languages in general (e.g. weak typing, associate arrays, “gluing”) and the scripting language at hand. Students might benefit from using the same framework (structure of programming elements and examples) for learning multiple scripting languages. Their existing programming skills should be reused while newly introduced scripting concepts should be reinforced in subsequent examples. 1 Introduction Scripting languages are popular for solving problems in many different domains [8]. Some are general scripting languages such as Perl, Python and Ruby, while others are slightly domain-specific (platform-specific: Bash, PowerShell) or very domain-specific (application-specific: Cfengine, Matlab). They can be characterized as high-level and weakly typed, as opposed to system programming languages such as Java and C++ [11]. In higher education, scripting languages are used both for introductory programming courses [14] and for lab exercises in later courses. It is in this last context the present work seeks to contribute to a better learning experience for students. Although much effort has been invested in researching ways of teaching introductory programming [12], the problem of how to convert existing programming skills to a new language seems slightly overlooked. The way this is solved in practice is by either providing a short tutorial style introduction to the new language, or referring the student to an online tutorial resource. -
Korn Shell Variables
V4.1 cover Front cover Korn and Bash Shell Programming (Course code AL32) Student Notebook ERC 1.0 IBM Certified Course Material Student Notebook Trademarks IBM® is a registered trademark of International Business Machines Corporation. The following are trademarks of International Business Machines Corporation in the United States, or other countries, or both: AIX® AIX 5L™ Language Environment® OS/2® POWER™ RISC System/6000® RS/6000® Java and all Java-based trademarks are trademarks of Sun Microsystems, Inc. in the United States, other countries, or both. Windows is a trademark of Microsoft Corporation in the United States, other countries, or both. UNIX® is a registered trademark of The Open Group in the United States and other countries. Linux® is a registered trademark of Linus Torvalds in the United States, other countries, or both. Other company, product, or service names may be trademarks or service marks of others. October 2007 edition The information contained in this document has not been submitted to any formal IBM test and is distributed on an “as is” basis without any warranty either express or implied. The use of this information or the implementation of any of these techniques is a customer responsibility and depends on the customer’s ability to evaluate and integrate them into the customer’s operational environment. While each item may have been reviewed by IBM for accuracy in a specific situation, there is no guarantee that the same or similar results will result elsewhere. Customers attempting to adapt these techniques to their own environments do so at their own risk. © Copyright International Business Machines Corporation 2007. -
User Commands Grep ( 1 ) Grep – Search a File for a Pattern /Usr/Bin/Grep [-Bchilnsvw] Limited-Regular-Expression [Filename
User Commands grep ( 1 ) NAME grep – search a file for a pattern SYNOPSIS /usr/bin/grep [-bchilnsvw] limited-regular-expression [filename...] /usr/xpg4/bin/grep [-E -F] [-c -l -q] [-bhinsvwx] -e pattern_list... [-f pattern_file]... [file...] /usr/xpg4/bin/grep [-E -F] [-c -l -q] [-bhinsvwx] [-e pattern_list...] -f pattern_file... [file...] /usr/xpg4/bin/grep [-E -F] [-c -l -q] [-bhinsvwx] pattern [file...] DESCRIPTION The grep utility searches text files for a pattern and prints all lines that contain that pattern. It uses a compact non-deterministic algorithm. Be careful using the characters $, ∗, [,ˆ,, (, ), and \ in the pattern_list because they are also meaning- ful to the shell. It is safest to enclose the entire pattern_list in single quotes ’ . ’. If no files are specified, grep assumes standard input. Normally, each line found is copied to standard output. The file name is printed before each line found if there is more than one input file. /usr/bin/grep The /usr/bin/grep utility uses limited regular expressions like those described on the regexp(5) manual page to match the patterns. /usr/xpg4/bin/grep The options -E and -F affect the way /usr/xpg4/bin/grep interprets pattern_list. If -E is specified, /usr/xpg4/bin/grep interprets pattern_list as a full regular expression (see -E for description). If -F is specified, grep interprets pattern_list as a fixed string. If neither are specified, grep interprets pattern_list as a basic regular expression as described on regex(5) manual page. OPTIONS The following options are supported for both /usr/bin/grep and /usr/xpg4/bin/grep: -b Precede each line by the block number on which it was found. -
Regular Expressions Grep and Sed Intro Previously
Lecture 4 Regular Expressions grep and sed intro Previously • Basic UNIX Commands – Files: rm, cp, mv, ls, ln – Processes: ps, kill • Unix Filters – cat, head, tail, tee, wc – cut, paste – find – sort, uniq – comm, diff, cmp – tr Subtleties of commands • Executing commands with find • Specification of columns in cut • Specification of columns in sort • Methods of input – Standard in – File name arguments – Special "-" filename • Options for uniq Today • Regular Expressions – Allow you to search for text in files – grep command • Stream manipulation: – sed Regular Expressions What Is a Regular Expression? • A regular expression (regex) describes a set of possible input strings. • Regular expressions descend from a fundamental concept in Computer Science called finite automata theory • Regular expressions are endemic to Unix – vi, ed, sed, and emacs – awk, tcl, perl and Python – grep, egrep, fgrep – compilers Regular Expressions • The simplest regular expressions are a string of literal characters to match. • The string matches the regular expression if it contains the substring. regular expression c k s UNIX Tools rocks. match UNIX Tools sucks. match UNIX Tools is okay. no match Regular Expressions • A regular expression can match a string in more than one place. regular expression a p p l e Scrapple from the apple. match 1 match 2 Regular Expressions • The . regular expression can be used to match any character. regular expression o . For me to poop on. match 1 match 2 Character Classes • Character classes [] can be used to match any specific set of characters. regular expression b [eor] a t beat a brat on a boat match 1 match 2 match 3 Negated Character Classes • Character classes can be negated with the [^] syntax. -
Linux Terminal Commands Man Pwd Ls Cd Olmo S
Python Olmo S. Zavala Romero Welcome Computers File system Super basics of Linux terminal Commands man pwd ls cd Olmo S. Zavala Romero mkdir touch Center of Atmospheric Sciences, UNAM rm mv Ex1 August 9, 2017 Regular expres- sions grep Ex2 More Python Olmo S. 1 Welcome Zavala Romero 2 Computers Welcome 3 File system Computers File system 4 Commands Commands man man pwd pwd ls ls cd mkdir cd touch mkdir rm touch mv Ex1 rm Regular mv expres- sions Ex1 grep Regular expressions Ex2 More grep Ex2 More Welcome to this course! Python Olmo S. Zavala Romero Welcome Computers File system Commands 1 Who am I? man pwd 2 Syllabus ls cd 3 Intro survey https://goo.gl/forms/SD6BM6KHKRlDOpZx1 mkdir 4 touch Homework 1 due this Sunday. rm mv Ex1 Regular expres- sions grep Ex2 More How does a computer works? Python Olmo S. Zavala Romero Welcome Computers File system Commands man pwd ls cd mkdir touch rm mv Ex1 Regular 1 CPU Central Processing Unit. All the computations happen there. expres- sions 2 HD Hard Drive. Stores persistent information in binary format. grep 3 RAM Random Access Memory. Faster memory, closer to the CPU, not persistent. Ex2 More 4 GPU Graphics Processing Unit. Used to process graphics. https://teentechdaily.files.wordpress.com/2015/06/computer-parts-diagram.jpg What is a file? Python Olmo S. Zavala Romero Welcome Computers File system Commands man pwd ls cd mkdir touch rm mv Section inside the HD with 0’s and 1’s. Ex1 Regular File extension is used to identify the meaning of those 0’s and 1’s. -
How to Build a Search-Engine with Common Unix-Tools
The Tenth International Conference on Advances in Databases, Knowledge, and Data Applications Mai 20 - 24, 2018 - Nice/France How to build a Search-Engine with Common Unix-Tools Andreas Schmidt (1) (2) Department of Informatics and Institute for Automation and Applied Informatics Business Information Systems Karlsruhe Institute of Technologie University of Applied Sciences Karlsruhe Germany Germany Andreas Schmidt DBKDA - 2018 1/66 Resources available http://www.smiffy.de/dbkda-2018/ 1 • Slideset • Exercises • Command refcard 1. all materials copyright, 2018 by andreas schmidt Andreas Schmidt DBKDA - 2018 2/66 Outlook • General Architecture of an IR-System • Naive Search + 2 hands on exercices • Boolean Search • Text analytics • Vector Space Model • Building an Inverted Index & • Inverted Index Query processing • Query Processing • Overview of useful Unix Tools • Implementation Aspects • Summary Andreas Schmidt DBKDA - 2018 3/66 What is Information Retrieval ? Information Retrieval (IR) is finding material (usually documents) of an unstructured nature (usually text) that satisfies an informa- tion need (usually a query) from within large collections (usually stored on computers). [Manning et al., 2008] Andreas Schmidt DBKDA - 2018 4/66 What is Information Retrieval ? need for query information representation how to match? document document collection representation Andreas Schmidt DBKDA - 2018 5/66 Keyword Search • Given: • Number of Keywords • Document collection • Result: • All documents in the collection, cotaining the keywords • (ranked by relevance) Andreas Schmidt DBKDA - 2018 6/66 Naive Approach • Iterate over all documents d in document collection • For each document d, iterate all words w and check, if all the given keywords appear in this document • if yes, add document to result set • Output result set • Extensions/Variants • Ranking see examples later ... -
Introduction to BASH: Part II
Introduction to BASH: Part II By Michael Stobb University of California, Merced February 17th, 2017 Quick Review ● Linux is a very popular operating system for scientific computing ● The command line interface (CLI) is ubiquitous and efficient ● A “shell” is a program that interprets and executes a user's commands ○ BASH: Bourne Again SHell (by far the most popular) ○ CSH: C SHell ○ ZSH: Z SHell ● Does everyone have access to a shell? Quick Review: Basic Commands ● pwd ○ ‘print working directory’, or where are you currently ● cd ○ ‘change directory’ in the filesystem, or where you want to go ● ls ○ ‘list’ the contents of the directory, or look at what is inside ● mkdir ○ ‘make directory’, or make a new folder ● cp ○ ‘copy’ a file ● mv ○ ‘move’ a file ● rm ○ ‘remove’ a file (be careful, usually no undos!) ● echo ○ Return (like an echo) the input to the screen ● Autocomplete! Download Some Example Files 1) Make a new folder, perhaps ‘bash_examples’, then cd into it. Capital ‘o’ 2) Type the following command: wget "goo.gl/oBFKrL" -O tutorial.tar 3) Extract the tar file with: tar -xf tutorial.tar 4) Delete the old tar file with rm tutorial.tar 5) cd into the new director ‘tutorial’ Input/Output Redirection ● Typically we give input to a command as follows: ○ cat file.txt ● Make the input explicit by using “<” ○ cat < file.txt ● Change the output by using “>” ○ cat < file.txt > output.txt ● Use the output of one function as the input of another ○ cat < file.txt | less BASH Utilities ● BASH has some awesome utilities ○ External commands not