DOCSLIB.ORG

CS101 Lecture 9

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
CS101 Lecture 9 How do you copy/move/rename/remove files? How do you create a directory ? What is redirection and piping? Readings: See CCSO’s Unix pages and 9-2 cp option file1 file2 First Version cp file1 file2 file3 … dirname Second Version This is one version of the cp command. file2 is created and the contents of file1 are copied into file2. If file2 already exits, it This version copies the files file1, file2, file3,… into the directory will be replaced with a new one. dirname. where option is -i Protects you from overwriting an existing file by asking you for a yes or no before it copies a file with an existing name. -r Can be used to copy directories and all their contents into a new directory 9-3 9-4 cs101 jsmith cs101 jsmith pwd data data mp1 pwd mp1 {FILES: mp1_data.m, mp1.m } {FILES: mp1_data.m, mp1.m } Copy the file named mp1_data.m from the cs101/data Copy the file named mp1_data.m from the cs101/data directory into the pwd. directory into the mp1 directory. > cp ~cs101/data/mp1_data.m . > cp ~cs101/data/mp1_data.m mp1 The (.) dot means “here”, that is, your pwd. 9-5 The (.) dot means “here”, that is, your pwd. 9-6 Example: To create a new directory named “temp” and to copy mv option file1 file2 First Version the contents of an existing directory named mp1 into temp, This is one version of the mv command. file1 is renamed file2. where option is -i Protects you from overwriting an existing file by asking you > cp -r mp1 temp for a yes or no before it copies a file with an existing name. This is useful to make a backup copy of your mp1 files. 9-7 9-8 mv file1 file2 file3 … dirname Third Version mv dirname1 dirname2 Second Version The files file1, file2, file3,… are moved into the directory dirname. In this version dirname1 is renamed dirname2 9-9 9-10 jsmith pwd rm option file1 file2 file3 … mp2 The rm command removes (deletes) each file in the list. temp source where option is -i For each file in the list, the user is asked whether or not to {FILES: mp2.c, mp2.h } {FILES: stat.c, input.dat } {FILES: edit.c } delete. -r Deletes a directory and every file or directory in it. Move all the files with .c suffix from the temp directory to the mp2 directory. Example: To delete a directory named temp and all its contents, > mv temp/*.c mp2 > rm -r temp Where temp is a subdirectory of the present working directory. Move the input.dat file into the home directory. Be very careful in using this command!!! > mv source/input.dat . 9-11 9-12 jsmith pwd mkdir dirname The mkdir command makes a subdirectory named dirname in mp2 workspace the present working directory. {FILES: mp2.c, main.c } Lab assignment: Create a directory named lab2 as a mp2 subdirectory of your home directory. Assuming that you are in your home directory, type Find all files named mp2.c . {FILES: mp2.c, main.c } >mkdir lab2 The mkdir creates a new directory but it does not cd for you. > find -name “mp2.c” -type f Find all directories named mp2 . > find -name “mp2” -type d 9-13 9-14 mp2 pwd Links commands to commands. Pipes are used to direct the output of one command to the input of the {FILES: mp2.c, input.c , stat.c, mp2.h, … } second. Unix uses the vertical bar “ | ” symbol to perform piping. General form > command1 | command2 You want to email your lab TA and send him/her all your files in the mp2 directory. > tar -czvf blah.tar.gz * creates a file named blah.tar.gz When your TA receives this file he/she can extract its contents by typing: > tar -xzvf blah.tar.gz 9-15 9-16 Example: when you use the ls command to list the contents of a directory the output may not fit on one full terminal screen. Since the screen scrolls you may not see the first part of the output. Use a pipe to solve this Links commands to a file. Redirection is used to take problem information that would normally be seen on the screen and > ls -la | more funnels it to a file or vice versa. Unix uses the “ > ” or “ < “ symbols to perform redirection. General form > command > filename output redirected to file filename > command < filename input from file filename not keyboard 9-18 Example: you can send the output from the ls command to a file” screen.txt ”. You can then use gedit to edit the file. passwd - change your password > ls -la > screen.txt clear - clears the terminal screen leaving the prompt > whoami - identity of the user man command - manual of information concerning command for example, type in “ man finger” to find all the options available for this command. 9-19 9-20 alias abbreviation command provides an alias for a command. alias abbreviation ‘ command1 command2 ’ provides an alias for compound commands For example, if you type, > alias dir ls -la For example, if you type, > alias dir ‘ls -la | more’ dir ls -la then is an alias for so if you type, > dir then dir is an alias for ls -la | more so if you type, > dir this is the same as typing in > ls -la this is the same as typing > ls -la | more To make this change effective each time you login, gedit the and this command displays the contents of the pwd one screen .cshrc file and type in the alias command. When you add a line at a time. at the end of the .cshrc file terminate the line by typing <return>. 9-21 9-22 alias abbreviation ‘ command1 \!* command2 ’ provides an How to: alias for compound commands and passes an argument. copy- cp/move - mv/rename - mv/remove-rm files. For example, if you type, Use the mkdir command to create a directory. > alias dir ‘ls -la \!* | more’ Redirection - uses the “<“ or “>” symbol. By default, then most commands expect input data from the keyboard and output data goes to the monitor. Using > dir lab1 redirection symbols, you can specify that the input comes from a file and output goes to a file. is the same as typing in > ls -la lab1 | more and this command displays the contents of the subdirectory of Piping - uses the “ | ” symbol. Output data from one the pwd named lab1, one screen at a time. command can be piped as into to another command. 9-23 9-24 .
Load more

Recommended publications
  • Autocad Command Aliases
    AutoCAD and Its Applications Advanced Appendix D AutoCAD Command Aliases Command Alias 3DALIGN 3AL 3DFACE 3F 3DMOVE 3M 3DORBIT 3DO, ORBIT, 3DVIEW, ISOMETRICVIEW 3DPOLY 3P 3DPRINT 3DP, 3DPLOT, RAPIDPROTOTYPE 3DROTATE 3R 3DSCALE 3S 3DWALK 3DNAVIGATE, 3DW ACTRECORD ARR ACTSTOP ARS -ACTSTOP -ARS ACTUSERINPUT ARU ACTUSERMESSAGE ARM -ACTUSERMESSAGE -ARM ADCENTER ADC, DC, DCENTER ALIGN AL ALLPLAY APLAY ANALYSISCURVATURE CURVATUREANALYSIS ANALYSISZEBRA ZEBRA APPLOAD AP ARC A AREA AA ARRAY AR -ARRAY -AR ATTDEF ATT -ATTDEF -ATT Copyright Goodheart-Willcox Co., Inc. Appendix D — AutoCAD Command Aliases 1 May not be reproduced or posted to a publicly accessible website. Command Alias ATTEDIT ATE -ATTEDIT -ATE, ATTE ATTIPEDIT ATI BACTION AC BCLOSE BC BCPARAMETER CPARAM BEDIT BE BLOCK B -BLOCK -B BOUNDARY BO -BOUNDARY -BO BPARAMETER PARAM BREAK BR BSAVE BS BVSTATE BVS CAMERA CAM CHAMFER CHA CHANGE -CH CHECKSTANDARDS CHK CIRCLE C COLOR COL, COLOUR COMMANDLINE CLI CONSTRAINTBAR CBAR CONSTRAINTSETTINGS CSETTINGS COPY CO, CP CTABLESTYLE CT CVADD INSERTCONTROLPOINT CVHIDE POINTOFF CVREBUILD REBUILD CVREMOVE REMOVECONTROLPOINT CVSHOW POINTON Copyright Goodheart-Willcox Co., Inc. Appendix D — AutoCAD Command Aliases 2 May not be reproduced or posted to a publicly accessible website. Command Alias CYLINDER CYL DATAEXTRACTION DX DATALINK DL DATALINKUPDATE DLU DBCONNECT DBC, DATABASE, DATASOURCE DDGRIPS GR DELCONSTRAINT DELCON DIMALIGNED DAL, DIMALI DIMANGULAR DAN, DIMANG DIMARC DAR DIMBASELINE DBA, DIMBASE DIMCENTER DCE DIMCONSTRAINT DCON DIMCONTINUE DCO, DIMCONT DIMDIAMETER DDI, DIMDIA DIMDISASSOCIATE DDA DIMEDIT DED, DIMED DIMJOGGED DJO, JOG DIMJOGLINE DJL DIMLINEAR DIMLIN, DLI DIMORDINATE DOR, DIMORD DIMOVERRIDE DOV, DIMOVER DIMRADIUS DIMRAD, DRA DIMREASSOCIATE DRE DIMSTYLE D, DIMSTY, DST DIMTEDIT DIMTED DIST DI, LENGTH DIVIDE DIV DONUT DO DRAWINGRECOVERY DRM DRAWORDER DR Copyright Goodheart-Willcox Co., Inc.
    [Show full text]
  • Common Commands Cheat Sheet by Mmorykan Via Cheatography.Com/89673/Cs/20411
    Common Commands Cheat Sheet by mmorykan via cheatography.com/89673/cs/20411/ Scripting Scripting (cont) GitHub bash filename - Runs script sleep value - Forces the script to wait value git clone <url​ > - Clones gitkeeper url Shebang - "#​ !bi​ n/b​ ash​ " - First line of bash seconds git add <fil​ ena​ me>​ - Adds the file to git script. Tells script what binary to use while [[ condition ]]; do stuff; done git commit - Commits all files to git ./file​ name - Also runs script if [[ condition ]]; do stuff; fi git push - Pushes all git files to host # - Creates a comment until [[ condition ]]; do stuff; done echo ${varia​ ble} - Prints variable words="​ h​ ouse dogs telephone dog" - Package / Networking hello_int = 1 - Treats "1​ " as a string Declares words array dnf upgrade - Updates system packages Use UPPERC​ ASE for constant variables for word in ${words} - traverses each dnf install - Installs package element in array Use lowerc​ ase​ _wi​ th_​ und​ ers​ cores for dnf search - Searches for package for counter in {1..10} - Loops 10 times regular variables dnf remove - Removes package for ((;;)) - Is infinite for loop echo $(( ${hello​ _int} + 1 )) - Treats hello_int systemctl start - Starts systemd service as an integer and prints 2 break - exits loop body systemctl stop - Stops systemd service mktemp - Creates temporary random file for ((count​ er=1; counter -le 10; counter​ ++)) systemctl restart - Restarts systemd service test - Denoted by "[[ condition ]]" tests the - Loops 10 times systemctl reload - Reloads systemd service condition
    [Show full text]
  • Shell Variables
    Shell Using the command line Orna Agmon ladypine at vipe.technion.ac.il Haifux Shell – p. 1/55 TOC Various shells Customizing the shell getting help and information Combining simple and useful commands output redirection lists of commands job control environment variables Remote shell textual editors textual clients references Shell – p. 2/55 What is the shell? The shell is the wrapper around the system: a communication means between the user and the system The shell is the manner in which the user can interact with the system through the terminal. The shell is also a script interpreter. The simplest script is a bunch of shell commands. Shell scripts are used in order to boot the system. The user can also write and execute shell scripts. Shell – p. 3/55 Shell - which shell? There are several kinds of shells. For example, bash (Bourne Again Shell), csh, tcsh, zsh, ksh (Korn Shell). The most important shell is bash, since it is available on almost every free Unix system. The Linux system scripts use bash. The default shell for the user is set in the /etc/passwd file. Here is a line out of this file for example: dana:x:500:500:Dana,,,:/home/dana:/bin/bash This line means that user dana uses bash (located on the system at /bin/bash) as her default shell. Shell – p. 4/55 Starting to work in another shell If Dana wishes to temporarily use another shell, she can simply call this shell from the command line: [dana@granada ˜]$ 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.
    [Show full text]
  • Unix (And Linux)
    AWK....................................................................................................................................4 BC .....................................................................................................................................11 CHGRP .............................................................................................................................16 CHMOD.............................................................................................................................19 CHOWN ............................................................................................................................26 CP .....................................................................................................................................29 CRON................................................................................................................................34 CSH...................................................................................................................................36 CUT...................................................................................................................................71 DATE ................................................................................................................................75 DF .....................................................................................................................................79 DIFF ..................................................................................................................................84
    [Show full text]
  • Laboratory 1: Getting Familiar with GLUE UNIX Programming Environment
    Laboratory 1: Getting Familiar with GLUE UNIX Programming Environment Lecture notes: 1. Scope of the course Prerequisite for ENEE 150 (see the last page for more details), very basic skills in programming and UNIX. a. Principles of programming and software development. b. C will be used as the programming language to illustrate the concepts. c. Basic skills in UNIX operating systems. 2. How to program (or develop software package in the future) a. Document everything you do in each of the following steps. b. Understand the project/problem requirements c. Develop algorithm (the way or method to solve the problem) d. Plan for the implementation of your algorithm (data structure, etc.) e. Write the programming (C, C++, Java, Matlab, etc.) f. Compile the program (gcc or cc in GLUE UNIX for C codes. Compiler is the interpreter that translates the program written in the so-called high level programming languages like C by human, who call themselves programmers, and understandable by human to the low level language that the computer understands.) g. Execute, test, and debug your program on sample data. h. Go back to step d. (modify your code) if necessary (programming or syntax bugs). i. Go back to step c. or step b. if there are serious problems (algorithm or logic bugs). j. Confirm that all the project requirements are met. (output format, etc.) 3. What is UNIX? a. UNIX is an operating system, like windows, which is a complex set of computer codes that manages the activities and resources of the computer. It is very popular in universities and colleges.
    [Show full text]
  • ANSWERS ΤΟ EVEN-Numbered
    8 Answers to Even-numbered Exercises 2.1. WhatExplain the following unexpected are result: two ways you can execute a shell script when you do not have execute permission for the file containing the script? Can you execute a shell script if you do not have read permission for the file containing the script? You can give the name of the file containing the script as an argument to the shell (for example, bash scriptfile or tcsh scriptfile, where scriptfile is the name of the file containing the script). Under bash you can give the following command: $ . scriptfile Under both bash and tcsh you can use this command: $ source scriptfile Because the shell must read the commands from the file containing a shell script before it can execute the commands, you must have read permission for the file to execute a shell script. 4.3. AssumeWhat is the purpose ble? you have made the following assignment: $ person=zach Give the output of each of the following commands. a. echo $person zach b. echo '$person' $person c. echo "$person" zach 1 2 6.5. Assumengs. the /home/zach/grants/biblios and /home/zach/biblios directories exist. Specify Zach’s working directory after he executes each sequence of commands. Explain what happens in each case. a. $ pwd /home/zach/grants $ CDPATH=$(pwd) $ cd $ cd biblios After executing the preceding commands, Zach’s working directory is /home/zach/grants/biblios. When CDPATH is set and the working directory is not specified in CDPATH, cd searches the working directory only after it searches the directories specified by CDPATH.
    [Show full text]
  • Linux Cheat Sheet
    1 of 4 ########################################### # 1.1. File Commands. # Name: Bash CheatSheet # # # # A little overlook of the Bash basics # ls # lists your files # # ls -l # lists your files in 'long format' # Usage: A Helpful Guide # ls -a # lists all files, including hidden files # # ln -s <filename> <link> # creates symbolic link to file # Author: J. Le Coupanec # touch <filename> # creates or updates your file # Date: 2014/11/04 # cat > <filename> # places standard input into file # Edited: 2015/8/18 – Michael Stobb # more <filename> # shows the first part of a file (q to quit) ########################################### head <filename> # outputs the first 10 lines of file tail <filename> # outputs the last 10 lines of file (-f too) # 0. Shortcuts. emacs <filename> # lets you create and edit a file mv <filename1> <filename2> # moves a file cp <filename1> <filename2> # copies a file CTRL+A # move to beginning of line rm <filename> # removes a file CTRL+B # moves backward one character diff <filename1> <filename2> # compares files, and shows where differ CTRL+C # halts the current command wc <filename> # tells you how many lines, words there are CTRL+D # deletes one character backward or logs out of current session chmod -options <filename> # lets you change the permissions on files CTRL+E # moves to end of line gzip <filename> # compresses files CTRL+F # moves forward one character gunzip <filename> # uncompresses files compressed by gzip CTRL+G # aborts the current editing command and ring the terminal bell gzcat <filename> #
    [Show full text]
  • UNIX Logout ^D Or Exit Man Command Man -K Keyword Ls Ls -A Ls -L Ls -G Cp
    UNIX Reference Page 1 of 3 UNIX Reference Computing and Information Technology Basic Commands Log out of system logout Exit current shell ^D or exit Online Documentation See online manual page man command Search for a manual page man -k keyword Files List filenames ls - with hidden files ls -a - with file permissions ls -l - with group ownership ls -g Copy a file cp old new Copy a file to dirname cp file dirname Rename (move) a file mv old new Remove (delete) a file rm file Append file1 to file2 cat file1 >> file2 Home directory ~ Home directory of user ~user Change file permissions chmod (ugo +-rwx) file Wild cards - single character ? - multiple characters * - range (a and b are single [a-b] characters) File Editors Emacs emacs file vi vi file pico pico file Using less View file less file next line <Return> next page <Space> search for pattern /pattern next occurrence n next file :n help :h http://wings.buffalo.edu/computing/Documentation/unix/ref/unixref.html 9/13/2004 UNIX Reference Page 2 of 3 quit :q Directories Make a directory mkdir dirname Change directories cd dirname Remove a directory rmdir dirname See thecurrent directory name pwd Current directory . Parent of the current directory .. Root of the file system / Printing Print file to default printer lpr file (Bell 101) Print file to a printer at another lpr -Pprintername site file View printer queue lpq -Pprinter Remove job number jn lprm jn View job turnaround time prstat Job and Process Control Run job j in the background j& List jobs jobs Connect to job number n %n List
    [Show full text]
  • Operating Systems 06R
    Operating Systems 06r. Assignment 5 Discussion Paul Krzyzanowski Rutgers University Spring 2015 March 9, 2015 © 2014-2015 Paul Krzyzanowski 1 Assignment 5 • Write a simple shell – Read one line: command and arguments – Run the command with the given arguments – Wait for the command to exit – Print the exit code of the command • You need to support built-in commands – cd dirname Change the current working directory to dirname – exit value Exit the shell. Optionally specify a value for the exit code March 9, 2015 © 2014-2015 Paul Krzyzanowski 2 What you need to support • You need to support built-in commands – cd dirname Change the current working directory to dirname – exit value Exit the shell. Optionally specify a value for the exit code • You need to support pipes – Pipe: ability to redirect the output of one program to the input of another program March 9, 2015 © 2014-2015 Paul Krzyzanowski 3 You do not need to support • A command that spans multiple lines • Background processes • Environment variables • Multiple commands per line – E.g.: pwd; echo hello; ls /; who • Programming constructs – E.g., while, for, if, do • I/O redirection – E.g., ls -l >outfile • Any other constructs not specifically mentioned March 9, 2015 © 2014-2015 Paul Krzyzanowski 4 Understanding pipes • Guiding philosophy in the design of Unix commands and the Unix shell – A set of small, well-defined commands – Each command does one thing – The output of a command should ideally be in a format that is useful as the input to another command (avoid headers and other
    [Show full text]
  • Configuring Your Login Session
    SSCC Pub.# 7-9 Last revised: 5/18/99 Configuring Your Login Session When you log into UNIX, you are running a program called a shell. The shell is the program that provides you with the prompt and that submits to the computer commands that you type on the command line. This shell is highly configurable. It has already been partially configured for you, but it is possible to change the way that the shell runs. Many shells run under UNIX. The shell that SSCC users use by default is called the tcsh, pronounced "Tee-Cee-shell", or more simply, the C shell. The C shell can be configured using three files called .login, .cshrc, and .logout, which reside in your home directory. Also, many other programs can be configured using the C shell's configuration files. Below are sample configuration files for the C shell and explanations of the commands contained within these files. As you find commands that you would like to include in your configuration files, use an editor (such as EMACS or nuTPU) to add the lines to your own configuration files. Since the first character of configuration files is a dot ("."), the files are called "dot files". They are also called "hidden files" because you cannot see them when you type the ls command. They can only be listed when using the -a option with the ls command. Other commands may have their own setup files. These files almost always begin with a dot and often end with the letters "rc", which stands for "run commands".
    [Show full text]
  • Configuration and Administration of Networking for Fedora 23
    Fedora 23 Networking Guide Configuration and Administration of Networking for Fedora 23 Stephen Wadeley Networking Guide Draft Fedora 23 Networking Guide Configuration and Administration of Networking for Fedora 23 Edition 1.0 Author Stephen Wadeley [email protected] Copyright © 2015 Red Hat, Inc. and others. The text of and illustrations in this document are licensed by Red Hat under a Creative Commons Attribution–Share Alike 3.0 Unported license ("CC-BY-SA"). An explanation of CC-BY-SA is available at http://creativecommons.org/licenses/by-sa/3.0/. The original authors of this document, and Red Hat, designate the Fedora Project as the "Attribution Party" for purposes of CC-BY-SA. In accordance with CC-BY-SA, if you distribute this document or an adaptation of it, you must provide the URL for the original version. Red Hat, as the licensor of this document, waives the right to enforce, and agrees not to assert, Section 4d of CC-BY-SA to the fullest extent permitted by applicable law. Red Hat, Red Hat Enterprise Linux, the Shadowman logo, JBoss, MetaMatrix, Fedora, the Infinity Logo, and RHCE are trademarks of Red Hat, Inc., registered in the United States and other countries. For guidelines on the permitted uses of the Fedora trademarks, refer to https://fedoraproject.org/wiki/ Legal:Trademark_guidelines. Linux® is the registered trademark of Linus Torvalds in the United States and other countries. Java® is a registered trademark of Oracle and/or its affiliates. XFS® is a trademark of Silicon Graphics International Corp. or its subsidiaries in the United States and/or other countries.
    [Show full text]
  • System Analysis and Tuning Guide System Analysis and Tuning Guide SUSE Linux Enterprise Server 15 SP1
    SUSE Linux Enterprise Server 15 SP1 System Analysis and Tuning Guide System Analysis and Tuning Guide SUSE Linux Enterprise Server 15 SP1 An administrator's guide for problem detection, resolution and optimization. Find how to inspect and optimize your system by means of monitoring tools and how to eciently manage resources. Also contains an overview of common problems and solutions and of additional help and documentation resources. Publication Date: September 24, 2021 SUSE LLC 1800 South Novell Place Provo, UT 84606 USA https://documentation.suse.com Copyright © 2006– 2021 SUSE LLC and contributors. All rights reserved. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or (at your option) version 1.3; with the Invariant Section being this copyright notice and license. A copy of the license version 1.2 is included in the section entitled “GNU Free Documentation License”. For SUSE trademarks, see https://www.suse.com/company/legal/ . All other third-party trademarks are the property of their respective owners. Trademark symbols (®, ™ etc.) denote trademarks of SUSE and its aliates. Asterisks (*) denote third-party trademarks. All information found in this book has been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. Neither SUSE LLC, its aliates, the authors nor the translators shall be held liable for possible errors or the consequences thereof. Contents About This Guide xii 1 Available Documentation xiii
    [Show full text]