Shell Scripting with Bash
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Windows Command Prompt Cheatsheet
Windows Command Prompt Cheatsheet - Command line interface (as opposed to a GUI - graphical user interface) - Used to execute programs - Commands are small programs that do something useful - There are many commands already included with Windows, but we will use a few. - A filepath is where you are in the filesystem • C: is the C drive • C:\user\Documents is the Documents folder • C:\user\Documents\hello.c is a file in the Documents folder Command What it Does Usage dir Displays a list of a folder’s files dir (shows current folder) and subfolders dir myfolder cd Displays the name of the current cd filepath chdir directory or changes the current chdir filepath folder. cd .. (goes one directory up) md Creates a folder (directory) md folder-name mkdir mkdir folder-name rm Deletes a folder (directory) rm folder-name rmdir rmdir folder-name rm /s folder-name rmdir /s folder-name Note: if the folder isn’t empty, you must add the /s. copy Copies a file from one location to copy filepath-from filepath-to another move Moves file from one folder to move folder1\file.txt folder2\ another ren Changes the name of a file ren file1 file2 rename del Deletes one or more files del filename exit Exits batch script or current exit command control echo Used to display a message or to echo message turn off/on messages in batch scripts type Displays contents of a text file type myfile.txt fc Compares two files and displays fc file1 file2 the difference between them cls Clears the screen cls help Provides more details about help (lists all commands) DOS/Command Prompt help command commands Source: https://technet.microsoft.com/en-us/library/cc754340.aspx. -
C Shell Scripts File Permissions a Simple Spelling Checker Command
Cshell scripts Asimple spelling checker mylatex1.csh #!/bin/csh #!/bin/csh tr -cs "[:alpha:]" "[\n*]" < $1 \ latex file.tex |tr"[:upper:]" "[:lower:]" \ dvips -f file.dvi > file.ps |sort -u > tempfile rm file.aux file.dvi file.log comm -23 tempfile /usr/share/dict/words rm tempfile mylatex2.csh #!/bin/csh Put one word per line \ |convert everything to lowercase \ latex $1.tex |sor t the words,remove duplicates and write the result to ’tempfile’. dvips -f $1.dvi > $1.ps rm $1.aux $1.dvi $1.log Pr int those words in ’tempfile’ that are not in the dictionary. Remove the temporar y file. Graham Kemp,Chalmers University of Technology Graham Kemp,Chalmers University of Technology File permissions Command substitution in a script ls -l To include the output from one command within the command line for another command, enclose the command whose output is to be included rwxrwx rwx within ‘backquotes‘. For example: rwxr -xr -x #!/bin/csh 111101101 echo Date and time is: date echo 1111 011 012 = 7558 echo "Your username is:" ‘whoami‘ echo "Your current directory is:" ‘pwd‘ chmod 755 file.sh chmod u+x file.sh chmod -R a+rX . Graham Kemp,Chalmers University of Technology Graham Kemp,Chalmers University of Technology Editing several files at once (1) sed scripts Suppose wewant to change ‘‘cie’’to‘‘cei’’inall files in the current grep href publications.html \ director y whose name ends with ‘‘.tex’’. |sed ’s/[ˆ"]*"//’ \ |sed ’s/".*//’ #!/bin/csh Instead of giving a single editing command on the command line,wecan ls *.tex | sed ’s/.*/sed s\/cie\/cei\/g & > &tmp/’ > s1 create a script file containing a sequence of editing commands. -
Shell Script & Advance Features of Shell Programming
Kirti Kaushik et al, International Journal of Computer Science and Mobile Computing, Vol.4 Issue.4, April- 2015, pg. 458-462 Available Online at www.ijcsmc.com International Journal of Computer Science and Mobile Computing A Monthly Journal of Computer Science and Information Technology ISSN 2320–088X IJCSMC, Vol. 4, Issue. 4, April 2015, pg.458 – 462 RESEARCH ARTICLE Shell Script & Advance Features of Shell Programming Kirti Kaushik* Roll No.15903, CS, Department of Computer science, Dronacharya College of Engineering, Gurgaon-123506, India Email: [email protected] Jyoti Yadav Roll No. 15040, CS, Department of Applied Computer science, Dronacharya College of Engineering, Gurgaon-123506, India Email: [email protected] Kriti Bhatia Roll No. 15048, CS, Department of Applied Computer science, Dronacharya College of Engineering, Gurgaon-123506, India Email: [email protected] Abstract-- In this research paper, the idea of shell scripting and writing computer programs is examined and different parts of shell programming are likewise contemplated. A shell script is a PC system intended to be controlled by the UNIX shell which is a charge line translator. The different tongues of shell scripts are thought to be scripting dialects. Regular operations performed by shell scripts incorporate document control, program execution, and printing content. A shell script can give an advantageous variety ofa framework order where unique environment settings, charge alternatives, or post-transforming apply naturally, yet in a manner that permits the new script to still go about as a completely typical UNIX summon. The real ideas like Programming in the Borne and C-shell, in which it would be clarified that how shell programming could be possible in Borne and C-shell. -
“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. -
Bash Crash Course + Bc + Sed + Awk∗
Bash Crash course + bc + sed + awk∗ Andrey Lukyanenko, CSE, Aalto University Fall, 2011 There are many Unix shell programs: bash, sh, csh, tcsh, ksh, etc. The comparison of those can be found on-line 1. We will primary focus on the capabilities of bash v.4 shell2. 1. Each bash script can be considered as a text file which starts with #!/bin/bash. It informs the editor or interpretor which tries to open the file, what to do with the file and how should it be treated. The special character set in the beginning #! is a magic number; check man magic and /usr/share/file/magic on existing magic numbers if interested. 2. Each script (assume you created “scriptname.sh file) can be invoked by command <dir>/scriptname.sh in console, where <dir> is absolute or relative path to the script directory, e.g., ./scriptname.sh for current directory. If it has #! as the first line it will be invoked by this command, otherwise it can be called by command bash <dir>/scriptname.sh. Notice: to call script as ./scriptname.sh it has to be executable, i.e., call command chmod 555 scriptname.sh before- hand. 3. Variable in bash can be treated as integers or strings, depending on their value. There are set of operations and rules available for them. For example: #!/bin/bash var1=123 # Assigns value 123 to var1 echo var1 # Prints ’var1’ to output echo $var1 # Prints ’123’ to output var2 =321 # Error (var2: command not found) var2= 321 # Error (321: command not found) var2=321 # Correct var3=$var2 # Assigns value 321 from var2 to var3 echo $var3 # Prints ’321’ to output -
The Linux Command Line
The Linux Command Line Fifth Internet Edition William Shotts A LinuxCommand.org Book Copyright ©2008-2019, William E. Shotts, Jr. This work is licensed under the Creative Commons Attribution-Noncommercial-No De- rivative Works 3.0 United States License. To view a copy of this license, visit the link above or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042. A version of this book is also available in printed form, published by No Starch Press. Copies may be purchased wherever fine books are sold. No Starch Press also offers elec- tronic formats for popular e-readers. They can be reached at: https://www.nostarch.com. Linux® is the registered trademark of Linus Torvalds. All other trademarks belong to their respective owners. This book is part of the LinuxCommand.org project, a site for Linux education and advo- cacy devoted to helping users of legacy operating systems migrate into the future. You may contact the LinuxCommand.org project at http://linuxcommand.org. Release History Version Date Description 19.01A January 28, 2019 Fifth Internet Edition (Corrected TOC) 19.01 January 17, 2019 Fifth Internet Edition. 17.10 October 19, 2017 Fourth Internet Edition. 16.07 July 28, 2016 Third Internet Edition. 13.07 July 6, 2013 Second Internet Edition. 09.12 December 14, 2009 First Internet Edition. Table of Contents Introduction....................................................................................................xvi Why Use the Command Line?......................................................................................xvi -
Powerview Command Reference
PowerView Command Reference TRACE32 Online Help TRACE32 Directory TRACE32 Index TRACE32 Documents ...................................................................................................................... PowerView User Interface ............................................................................................................ PowerView Command Reference .............................................................................................1 History ...................................................................................................................................... 12 ABORT ...................................................................................................................................... 13 ABORT Abort driver program 13 AREA ........................................................................................................................................ 14 AREA Message windows 14 AREA.CLEAR Clear area 15 AREA.CLOSE Close output file 15 AREA.Create Create or modify message area 16 AREA.Delete Delete message area 17 AREA.List Display a detailed list off all message areas 18 AREA.OPEN Open output file 20 AREA.PIPE Redirect area to stdout 21 AREA.RESet Reset areas 21 AREA.SAVE Save AREA window contents to file 21 AREA.Select Select area 22 AREA.STDERR Redirect area to stderr 23 AREA.STDOUT Redirect area to stdout 23 AREA.view Display message area in AREA window 24 AutoSTOre .............................................................................................................................. -
Shell Variables
Shell Using the command line Orna Agmon ladypine at vipe.technion.ac.il Haifux Shell – p. 1/55 TOC Various shells Customizing the shell getting help and information Combining simple and useful commands output redirection lists of commands job control environment variables Remote shell textual editors textual clients references Shell – p. 2/55 What is the shell? The shell is the wrapper around the system: a communication means between the user and the system The shell is the manner in which the user can interact with the system through the terminal. The shell is also a script interpreter. The simplest script is a bunch of shell commands. Shell scripts are used in order to boot the system. The user can also write and execute shell scripts. Shell – p. 3/55 Shell - which shell? There are several kinds of shells. For example, bash (Bourne Again Shell), csh, tcsh, zsh, ksh (Korn Shell). The most important shell is bash, since it is available on almost every free Unix system. The Linux system scripts use bash. The default shell for the user is set in the /etc/passwd file. Here is a line out of this file for example: dana:x:500:500:Dana,,,:/home/dana:/bin/bash This line means that user dana uses bash (located on the system at /bin/bash) as her default shell. Shell – p. 4/55 Starting to work in another shell If Dana wishes to temporarily use another shell, she can simply call this shell from the command line: [dana@granada ˜]$ bash dana@granada:˜$ #In bash now dana@granada:˜$ exit [dana@granada ˜]$ bash dana@granada:˜$ #In bash now, going to hit ctrl D dana@granada:˜$ exit [dana@granada ˜]$ #In original shell now Shell – p. -
Examining the Hamilton C Shell
EXAMINING ROO M Examining the Hamilton C Shell Unix power for OS/2 Scott Richman tarting OS/2 for the first time was, file system), long filenames, and threads. in the background and the server will for me, like unlocking a Ferarri, Additionally, the Shell supports large be kept busy. sitting behind its wheel and find command lines and pipes (up to 64K) ing a Yugo's dash. What a disap and includes faster and more powerful Supporting Procedures pointment. Sure, the engine and utilities than those supplied with OS/2. Script programmers can create C Shell suspensionS were first rate, but the con This is more than Unix - this is a pow procedures, which are more like func trols were minimal, the clutch was stiff, erful requirement for development un tions: They accept a parameter list and and the pedals were nonresponsive! der OS/2. The ability to execute C shells return a value. These procedures are OS/2 comes with great stuff, but CMD simultaneously in different Presenta compiled into C Shell memory and are .EXE, the default command-line pro tion Manager (PM) text windows con then executed as new shell commands. cessor, is poor compared to the pow verts your PC into a flexible workstation. Procedures can greatly extend the erfuloperating system beneath. CMD.EXE The Hamilton C Shell comes with power and flexibility of your environ appears to be a port of the MS-DOS many programs and shell scripts. To ment. COMMAND.COM and lacks the major install the Shell, you simply copy the As an example, consider ZCW.CSH features of a serious front end. -
Shell Script Getopts Example
Shell Script Getopts Example Gail is constrainedly cryoscopic after delegable Hilbert sag his parcloses illuminatingly. Gonzales often tootle irresistibly when tripersonal Giordano discomposed dissonantly and buffer her Barbarossa. Robert misdraws rompishly. Find that getopts script example we use later will contain whitespace separation with command Instantly share code, notes, and snippets. OPTARG is set to the period character found. They cease in many cases unneeded and brief fact that cartoon always press them its just like matter of personal coding style. File or directory or found. Operator precedence is used when there within five is more arguments. Typically, shell scripts use getopts to parse arguments passed to them. There did many ways to against your remedy environment. Nothing gets printed when no command line options are provided. The return status is zero unless an outcome is encountered while determining the name avid the he directory within an invalid option is supplied. The exit code will be success failure. Log in charge use details from one require these accounts. How does log lumber and cpu usage by an application? Now consider running it bore an unsupported option. No need only pass the positional parameters through to borrow external program. How can I check took a directory exists in a candy shell script? What extent its purpose? When optional, the fashion can buckle on led off additional functionality, as ugly a boolean option. In those cases, it contains a pointer to that parameter. How environment check ride a variable is set to Bash? Connect and deploy knowledge write a single location that is structured and fatigue to search. -
UNIX X Command Tips and Tricks David B
SESUG Paper 122-2019 UNIX X Command Tips and Tricks David B. Horvath, MS, CCP ABSTRACT SAS® provides the ability to execute operating system level commands from within your SAS code – generically known as the “X Command”. This session explores the various commands, the advantages and disadvantages of each, and their alternatives. The focus is on UNIX/Linux but much of the same applies to Windows as well. Under SAS EG, any issued commands execute on the SAS engine, not necessarily on the PC. X %sysexec Call system Systask command Filename pipe &SYSRC Waitfor Alternatives will also be addressed – how to handle when NOXCMD is the default for your installation, saving results, and error checking. INTRODUCTION In this paper I will be covering some of the basics of the functionality within SAS that allows you to execute operating system commands from within your program. There are multiple ways you can do so – external to data steps, within data steps, and within macros. All of these, along with error checking, will be covered. RELEVANT OPTIONS Execution of any of the SAS System command execution commands depends on one option's setting: XCMD Enables the X command in SAS. Which can only be set at startup: options xcmd; ____ 30 WARNING 30-12: SAS option XCMD is valid only at startup of the SAS System. The SAS option is ignored. Unfortunately, ff NOXCMD is set at startup time, you're out of luck. Sorry! You might want to have a conversation with your system administrators to determine why and if you can get it changed. -
An Empirical Comparison of Widely Adopted Hash Functions in Digital Forensics: Does the Programming Language and Operating System Make a Difference?
2015 Annual ADFSL Conference on Digital Forensics, Security and Law Proceedings May 19th, 11:45 AM An Empirical Comparison of Widely Adopted Hash Functions in Digital Forensics: Does the Programming Language and Operating System Make a Difference? Satyendra Gurjar Cyber Forensics Research and Education Group (UNHcFREG), Tagliatela College of Engineering, ECECS Department, University of New Haven, [email protected] Ibrahim Baggili Cyber Forensics Research and Education Group (UNHcFREG), Tagliatela College of Engineering, ECECS Department, University of New Haven Frank Breitinger CyberFollow F thisorensics and additional Research worksand Education at: https:/ Gr/commons.eroup (UNHcFREG),au.edu/adfsl Tagliatela College of Engineering, ECECS Depar Partment,t of the Univ Aviationersity ofSaf Newety and Hav Securityen Commons, Computer Law Commons, Defense and Security AliceStudies Fischer Commons , Forensic Science and Technology Commons, Information Security Commons, CyberNational For Securityensics Resear Law Commonsch and Education, OS and GrNetworksoup (UNHcFREG), Commons T, Otheragliatela Computer College Sciences of Engineering, Commons ECECS, and theDepar Socialtment, Contr Univol,ersity Law , ofCrime, New andHav enDe,viance AFischer@newha Commons ven.edu Scholarly Commons Citation Gurjar, Satyendra; Baggili, Ibrahim; Breitinger, Frank; and Fischer, Alice, "An Empirical Comparison of Widely Adopted Hash Functions in Digital Forensics: Does the Programming Language and Operating System Make a Difference?" (2015). Annual ADFSL Conference on Digital Forensics, Security and Law. 6. https://commons.erau.edu/adfsl/2015/tuesday/6 This Peer Reviewed Paper is brought to you for free and open access by the Conferences at Scholarly Commons. It has been accepted for inclusion in Annual ADFSL Conference on Digital Forensics, Security and Law by an (c)ADFSL authorized administrator of Scholarly Commons.