Operating Systems and Using Linux

Slides:



Advertisements
Similar presentations
Cosc 4750 Getting Started in UNIX Don’t be afraid of the prompt, in linux it can be your best friend. In some cases, the only way to do certain things.
Advertisements

Exploring the UNIX File System and File Security
Introducing the Command Line CMSC 121 Introduction to UNIX Much of the material in these slides was taken from Dan Hood’s CMSC 121 Lecture Notes.
Linux+ Guide to Linux Certification, Second Edition
The UNIX File System.
A Mini UNIX Tutorial. What’s UNIX?  An operating system run on many servers/workstations  Invented by AT&T Bell Labs in late 60’s  Currently there.
CMSC 104, L031 Operating Systems and Using Linux Topics What is an Operating System? Linux Overview Frequently Used Linux Commands Reading None.
Overview of Linux CS3530 Spring 2014 Dr. José M. Garrido Department of Computer Science.
1 THE UNIX FILE SYSTEM By Chokechai Chuensukanant ID COSC 513 Operating System.
Unix Primer. Unix Shell The shell is a command programming language that provides an interface to the UNIX operating system. The shell is a “regular”
Lesson 7-Creating and Changing Directories. Overview Using directories to create order. Managing files in directories. Using pathnames to manage files.
Chapter 9 Part II Linux Command Line Access to Linux Authenticated login using a Linux account is required to access a Linux system. The Linux prompt will.
1 Lecture 2 Working with Files and Directories COP 3344 Introduction to UNIX.
Cmsc 312 Operating Systems. UNIX? DOS – PC? VAX/VMS - mainframe Unix – PC, workstation, mainframe 1970 bell Lab For computer scientist? Why popular? Free.
CS240 Computer Science II Introduction the Unix File System and File Related Utilities Based on “UNIX for Programmers and Users” by G.Class and K. Ables.
Chapter Two Exploring the UNIX File System and File Security.
1 Operating Systems and Using Linux Topics What is an Operating System? Linux Overview Frequently Used Linux Commands Some content in this lecture added.
Operating Systems and Using Linux CMSC 104, Lecture 3 John Y. Park 1.
1 Operating Systems and Using Linux Topics What is an Operating System? Linux Overview Frequently Used Linux Commands Reading None.
BIF713 Basic Unix/Linux Commands Getting Help with Commands.
8-2 What is a program? What is a “Window Manager” ? What is a “GUI” ? How do you navigate the Unix directory tree? What is a wildcard? Readings: See CCSO’s.
Agenda Basic Unix Commands (Chapters 2 & 3) Miscellaneous Commands: whereis, which, whoami, finger, passwd, cal, date Working with Files: cat, more, less.
Introduction to Programming Using C An Introduction to Operating Systems.
1 Lecture 2 Working with Files and Directories COP 3353 Introduction to UNIX.
Agenda The Linux File System (chapter 4 in text)
BIF713 File and Directory Management. File System A File System is a structure used to organize programs and data on a computer ’ s storage device Files.
Isecur1ty training center Presented by : Eng. Mohammad Khreesha.
CMSC 104, Section 301, Fall Lecture 04, 9/11/02 Operating Systems and Using Linux Review Operating System. Linux Overview. Frequently Used Linux.
Linux+ Guide to Linux Certification, Second Edition Chapter 4 Exploring Linux Filesystems.
 Last lesson, the Windows Operating System was discussed along with the Windows command shell  Unix is a computer operating system, that similarly manages.
Learning basic Unix command It 325 operating system.
CMSC 104, Section 301, Fall Lecture 03, 9/09/02 Operating Systems and Using Linux Topics Review Number Systems. Go over Homework 1 Solution. CSHC.
Operating Systems and Using Linux Courtesy of John Y. Park 1.
CMSC 104, Version 8/061L03OperatingSystems.ppt Operating Systems and Using Linux Topics What is an Operating System? Linux Overview Frequently Used Linux.
Agenda The Linux File System (chapter 4 in text) Directory Structures / Navigation Terminology File Naming Rules Relative vs Absolute pathnames Unix Commands:
CMSC 104, Version 9/011 Operating Systems and Using Linux Topics What is an Operating System? Linux Overview Frequently Used Linux Commands Reading None.
UMBC CMSC 104 – Section 01, Fall 2016
Overview of Linux Fall 2016 Dr. Donghyun Kim
Agenda The Linux File System (chapter 4 in text)
UNIX To do work for the class, you will be using the Unix operating system. Once connected to the system, you will be presented with a login screen. Once.
Commands Basic syntax of shell commands UNIX or shell commands have a basic structure command -options target command comes first (such as cd or ls) any.
Web Programming Essentials:
Andy Wang Object Oriented Programming in C++ COP 3330
Computing Fundamenatls CMSC 201 Computer Science I Penny Rheingans University of Maryland Baltimore County (with inspiration from previous 201 instructors.
Lecture 2 Working with Files and Directories
The Command Prompt Commands are the way to “do things” in Unix
Tools of Web Development 1: Module C: Using Unix
UNIX Basics Internet Technology.
Operating Systems and Using Linux
Operating Systems and Using Linux
Operating Systems and Using Linux
Exploring the UNIX File System and File Security
Operating Systems and Using Linux
Introduction to Linux Week 0 - Thursday.
Unix : Introduction and Commands
Operating Systems and Using Linux
Operating Systems and Using Linux
Web Programming Essentials:
The Unix File System.
Operating Systems and Using Linux
Operating Systems and Using Linux
Operating Systems and Using Linux
UNIX/LINUX Commands Using BASH Copyright © 2017 – Curt Hill.
Operating Systems and Using Linux
Operating Systems and Using Linux
Module 6 Working with Files and Directories
What is Unix? A multi-user networked operating system
Operating Systems and Using Linux
January 26th, 2004 Class Meeting 2
Presentation transcript:

Operating Systems and Using Linux Topics What is an Operating System? Linux Overview Frequently Used Linux Commands

What is an Operating System? A computer program that: Controls how the CPU, memory and I/O devices work together to execute programs Performs many operations, such as: Allows you to communicate with the computer (tell it what to do)‏ Controls access (login) to the computer Keeps track of all processes currently running Often referred to as simply OS

How Do I Communicate With the Computer Using the OS? You communicate using the particular OS’s user interface. Graphical User Interface (GUI) – Windows, Linux Command-driven interface - DOS, UNIX, Linux We will be using the Linux operating system, which is very similar to UNIX. Notice that it is listed as both GUI and Command-driven.

GUI vs. Command-driven We will be using both the GUI version of Linux and the Command-driven Interface. When you connect to GL through TeraTerm, you are using only the Command-driven Interface. When you reboot the computer into Linux, you will use both the GUI and the Command- driven Interface.

Example of Command-driven Screenshot of connection to linux3.gl.umbc.edu

Example of GUI Screenshot of Fedora 7

Screenshot of Red Hat Enterprise Linux (RHEL) 5 Another Example of GUI Screenshot of Red Hat Enterprise Linux (RHEL) 5

How Do I Communicate With the Computer Using the OS? (con’t)‏ When you log in to the Linux system here, a user prompt will be displayed: where # is the number of the Linux server to which you have connected. You may use any of the Linux servers: linux1, linux2 or linux3. The number in the brackets will change as you work. It is the “number” of the command that you are about to type. If this prompt is not on the screen at any time, you are not communicating with the OS. linux#[1]% _

Linux Overview Files and Filenames Directories and Subdirectories Frequently Used Commands

Files A file is a sequence of bytes. It can be created by a text editor (XEmacs or Notepad)‏ a computer program (such as a C program)‏ It may contain a program, data, a document, or other information . Files that contain other files are called directories (sometimes called folders).

Linux Filenames Restrictions Typically do not have spaces or other reserved characters Have a maximum length (typically 255 characters but who wants to type that much!)‏ Are case sensitive For this class, you should stick with filenames that contain only letters (uppercase or lowercase), numbers, and the underscore ( _ ) or hypen (-). No spaces! Some examples: firefox.exe, things2do.txt, dinner_menu.pdf

Directories Directories contain files or other directories called subdirectories. They may also be empty. Directories are organized in a hierarchical fashion. They help us to keep our files organized.

Example Directory Tree /afs/umbc.edu/users/j/d/jdoe28/home/ Mail/ recipes/ courses/ pies/ cookies/ CMSC104/ apple.txt peach.txt choc_chip.txt

Subdirectories Are used for organizing your files For example, make a subdirectory for CMSC104 make subdirectories for each project CMSC104/ hw1/ hw3/ ... proj4/

More Directories Your home directory is where you are located when you log in (e.g., /afs/umbc.edu/users/j/d/jdoe28/home/). The current directory is where you are located at any time while you are using the system. The / (pronounced “slash”) is the root directory in Linux. Files within the same directory must be given unique names. Paths allow us to give the same name to different files located in different directories. Each running program has a current directory and all filenames are implicitly assumed to start with the name of that directory unless they begin with a slash.

Moving in the Directory Tree . (dot) is the current directory. . . (dot-dot) is the parent directory. Use the Linux command cd to change directories. Use dot-dot to move up the tree. cd .. Use the directory name to move down. cd recipes Use the complete directory name (path name) to move anywhere. cd /afs/umbc.edu/users/j/d/jdoe28/home/recipes/

/afs/umbc.edu/users/j/d/jdoe28/home/recipes/ Absolute Path The absolute path is a path that contains the root directory and all other subdirectories you need to access the file It points to the same location in the directory tree regardless of the current working directory An example of an absolute path /afs/umbc.edu/users/j/d/jdoe28/home/recipes/ Starts with /

Relative Path The relative path is a partial path to a file in relation to the current working directory If inside of the home directory in the previous directory example, a relative path would be recipes/cookies/ Does not start with /

Frequently Used Linux Commands passwd, man, lpr pwd, ls, cat, more, cd, cp, mv, rm, mkdir, rmdir ctrl-c References: Linux man page Links from the 104 homepage Books and the Internet Time to take notes!

Wildcard Characters You will find wildcard characters useful when manipulating files (e.g., listing or moving them). The wildcard characters are * and ? ? is used to represent any single character. For example, ls hw?.txt would match the files hw1.txt and hw2.txt but not hw123.txt * is used to represent 0 or more characters. For example, ls hw*.txt would match the files hw1.txt and hw2.txt, as well as hw.txt, hw123.txt and hw_assignment.txt