Case Statement in Shell Script
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Shell Scripting with Bash
Introduction to Shell Scripting with Bash Charles Jahnke Research Computing Services Information Services & Technology Topics for Today ● Introductions ● Basic Terminology ● How to get help ● Command-line vs. Scripting ● Variables ● Handling Arguments ● Standard I/O, Pipes, and Redirection ● Control Structures (loops and If statements) ● SCC Job Submission Example Research Computing Services Research Computing Services (RCS) A group within Information Services & Technology at Boston University provides computing, storage, and visualization resources and services to support research that has specialized or highly intensive computation, storage, bandwidth, or graphics requirements. Three Primary Services: ● Research Computation ● Research Visualization ● Research Consulting and Training Breadth of Research on the Shared Computing Cluster (SCC) Me ● Research Facilitator and Administrator ● Background in biomedical engineering, bioinformatics, and IT systems ● Offices on both CRC and BUMC ○ Most of our staff on the Charles River Campus, some dedicated to BUMC ● Contact: [email protected] You ● Who has experience programming? ● Using Linux? ● Using the Shared Computing Cluster (SCC)? Basic Terminology The Command-line The line on which commands are typed and passed to the shell. Username Hostname Current Directory [username@scc1 ~]$ Prompt Command Line (input) The Shell ● The interface between the user and the operating system ● Program that interprets and executes input ● Provides: ○ Built-in commands ○ Programming control structures ○ Environment -
Object Oriented Programming
No. 52 March-A pril'1990 $3.95 T H E M TEe H CAL J 0 URN A L COPIA Object Oriented Programming First it was BASIC, then it was structures, now it's objects. C++ afi<;ionados feel, of course, that objects are so powerful, so encompassing that anything could be so defined. I hope they're not placing bets, because if they are, money's no object. C++ 2.0 page 8 An objective view of the newest C++. Training A Neural Network Now that you have a neural network what do you do with it? Part two of a fascinating series. Debugging C page 21 Pointers Using MEM Keep C fro111 (C)rashing your system. An AT Keyboard Interface Use an AT keyboard with your latest project. And More ... Understanding Logic Families EPROM Programming Speeding Up Your AT Keyboard ((CHAOS MADE TO ORDER~ Explore the Magnificent and Infinite World of Fractals with FRAC LS™ AN ELECTRONIC KALEIDOSCOPE OF NATURES GEOMETRYTM With FracTools, you can modify and play with any of the included images, or easily create new ones by marking a region in an existing image or entering the coordinates directly. Filter out areas of the display, change colors in any area, and animate the fractal to create gorgeous and mesmerizing images. Special effects include Strobe, Kaleidoscope, Stained Glass, Horizontal, Vertical and Diagonal Panning, and Mouse Movies. The most spectacular application is the creation of self-running Slide Shows. Include any PCX file from any of the popular "paint" programs. FracTools also includes a Slide Show Programming Language, to bring a higher degree of control to your shows. -
Name Synopsis Description
Perl version 5.10.0 documentation - vmsish NAME vmsish - Perl pragma to control VMS-specific language features SYNOPSIS use vmsish; use vmsish 'status';# or '$?' use vmsish 'exit'; use vmsish 'time'; use vmsish 'hushed'; no vmsish 'hushed'; vmsish::hushed($hush); use vmsish; no vmsish 'time'; DESCRIPTION If no import list is supplied, all possible VMS-specific features areassumed. Currently, there are four VMS-specific features available:'status' (a.k.a '$?'), 'exit', 'time' and 'hushed'. If you're not running VMS, this module does nothing. vmsish status This makes $? and system return the native VMS exit statusinstead of emulating the POSIX exit status. vmsish exit This makes exit 1 produce a successful exit (with status SS$_NORMAL),instead of emulating UNIX exit(), which considers exit 1 to indicatean error. As with the CRTL's exit() function, exit 0 is also mappedto an exit status of SS$_NORMAL, and any other argument to exit() isused directly as Perl's exit status. vmsish time This makes all times relative to the local time zone, instead of thedefault of Universal Time (a.k.a Greenwich Mean Time, or GMT). vmsish hushed This suppresses printing of VMS status messages to SYS$OUTPUT andSYS$ERROR if Perl terminates with an error status. and allowsprograms that are expecting "unix-style" Perl to avoid having to parseVMS error messages. It does not suppress any messages from Perlitself, just the messages generated by DCL after Perl exits. The DCLsymbol $STATUS will still have the termination status, but with ahigh-order bit set: EXAMPLE:$ perl -e"exit 44;" Non-hushed error exit%SYSTEM-F-ABORT, abort DCL message$ show sym $STATUS$STATUS == "%X0000002C" $ perl -e"use vmsish qw(hushed); exit 44;" Hushed error exit $ show sym $STATUS $STATUS == "%X1000002C" The 'hushed' flag has a global scope during compilation: the exit() ordie() commands that are compiled after 'vmsish hushed' will be hushedwhen they are executed. -
Using the GNU Compiler Collection (GCC)
Using the GNU Compiler Collection (GCC) Using the GNU Compiler Collection by Richard M. Stallman and the GCC Developer Community Last updated 23 May 2004 for GCC 3.4.6 For GCC Version 3.4.6 Published by: GNU Press Website: www.gnupress.org a division of the General: [email protected] Free Software Foundation Orders: [email protected] 59 Temple Place Suite 330 Tel 617-542-5942 Boston, MA 02111-1307 USA Fax 617-542-2652 Last printed October 2003 for GCC 3.3.1. Printed copies are available for $45 each. Copyright c 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 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 1.2 or any later version published by the Free Software Foundation; with the Invariant Sections being \GNU General Public License" and \Funding Free Software", the Front-Cover texts being (a) (see below), and with the Back-Cover Texts being (b) (see below). A copy of the license is included in the section entitled \GNU Free Documentation License". (a) The FSF's Front-Cover Text is: A GNU Manual (b) The FSF's Back-Cover Text is: You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development. i Short Contents Introduction ...................................... 1 1 Programming Languages Supported by GCC ............ 3 2 Language Standards Supported by GCC ............... 5 3 GCC Command Options ......................... -
Introduction to Unix
Introduction to Unix Rob Funk <[email protected]> University Technology Services Workstation Support http://wks.uts.ohio-state.edu/ University Technology Services Course Objectives • basic background in Unix structure • knowledge of getting started • directory navigation and control • file maintenance and display commands • shells • Unix features • text processing University Technology Services Course Objectives Useful commands • working with files • system resources • printing • vi editor University Technology Services In the Introduction to UNIX document 3 • shell programming • Unix command summary tables • short Unix bibliography (also see web site) We will not, however, be covering these topics in the lecture. Numbers on slides indicate page number in book. University Technology Services History of Unix 7–8 1960s multics project (MIT, GE, AT&T) 1970s AT&T Bell Labs 1970s/80s UC Berkeley 1980s DOS imitated many Unix ideas Commercial Unix fragmentation GNU Project 1990s Linux now Unix is widespread and available from many sources, both free and commercial University Technology Services Unix Systems 7–8 SunOS/Solaris Sun Microsystems Digital Unix (Tru64) Digital/Compaq HP-UX Hewlett Packard Irix SGI UNICOS Cray NetBSD, FreeBSD UC Berkeley / the Net Linux Linus Torvalds / the Net University Technology Services Unix Philosophy • Multiuser / Multitasking • Toolbox approach • Flexibility / Freedom • Conciseness • Everything is a file • File system has places, processes have life • Designed by programmers for programmers University Technology Services -
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. -
Seashore Guide
Seashore The Incomplete Guide Contents Contents..........................................................................................................................1 Introducing Seashore.......................................................................................................4 Product Summary........................................................................................................4 Technical Requirements ..............................................................................................4 Development Notice....................................................................................................4 Seashore’s Philosophy.................................................................................................4 Seashore and the GIMP...............................................................................................4 How do I contribute?...................................................................................................5 The Concepts ..................................................................................................................6 Bitmaps.......................................................................................................................6 Colours .......................................................................................................................7 Layers .........................................................................................................................7 Channels .................................................................................................................. -
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. -
Shells and Shell Scripting
Shells and Shell scripting What is a Shell? • A shell is a command line interpreter that is the interface between the user and the OS. • A “program launcher” of sorts. • The shell: o analyzes each command o determines what actions are to be performed o performs the actions • Example: wc –l file1 > file2 Which shell? • sh – Bourne shell o Most common, other shells are a superset o Good for programming • csh or tcsh – default for command line on CDF o C-like syntax o Best for interactive use. Not good for programming. • bash – default on Linux (Bourne again shell) o Based on sh, with some csh features. • korn – written by David Korn o Based on sh – Some claim best for programming. o Commercial product. Common shell facilities Shell startup When a shell is invoked, it does the following: 1. Read a special startup file (usually in home directory) 2. display prompt and wait for command 3. Ctrl-D on its own line terminates shell, otherwise, goto step 2. Shell startup files used to set shell options, set up environment variables, alias sh – executes .profile if it’s there. ksh – executes .profile if in interactive mode. Executes $ENV (usually $HOME/.kshrc) csh – executes .cshrc if it exists. If a login shell, executes .login bash – executes .bashrc, if a login shell, executes .bash_profile instead Executables vs. built-in commands Most commands you run are other compiled programs. Found in /bin Example: ls – shell locates ls binary in /bin directory and launches it Some are not compiled programs, but built into the shell: cd, echo Input-output redirection prog < infile > outfile ls > outfile 2>&1 # sh stdout and stderr Pipelining commands send the output from one command to the input of the next: ls -l | wc ps –aux | grep reid | sort Before a program is executed, the shell recognizes the special characters such as <, >, |, and rewires the standard input, output, or error file descriptors of the program about to be executed to point to the right files (or the standard input of another program). -
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. -
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