Instructor: Xiuwen Liu Department of Computer Science COP 4610:Introduction to Operating Systems CGS 5765: Principles of Operating Systems Instructor: Xiuwen Liu Department of Computer Science Florida State University Please pick up the syllabus from the front

Outline Class organization Programming environment at Computer Science Syllabus Programming environment at Computer Science Introduction to Operating Systems A survey 5/7/2019 COP4610

Class organization Class syllabus Class web page Comments Grading Academic honor code Programs you submitted must be your own While discussions of class materials and assignments are allowed, discussion and copying of solutions is strictly prohibited. 5/7/2019 COP4610

Class Email List Class email list I sent a message with the subject “We are going to have the first recitation on Aug. 27” on Monday, Aug. 25 If you have not received the email, or would like to use another email, please send me an email with your email address Some of you did not receive the message because of problems such as wrong email address in your record I will send important announcements through the mailing list 5/7/2019 COP4610

Recitation Session Recitation session will be taught by the instructor You are required to attend the same session as you registered Recitation session will focus on Questions and answers Programming examples First recitation session is this Wednesday, Aug. 27. 5/7/2019 COP4610

Textbook You are required to read the chapters in the textbook You can skip sections only when specified You are NOT required to read programming examples in the dotted boxes However, you are required to know programming examples given in class and those related to programming projects You may be tested on the materials in the textbook but not fully covered in the class I will specify those sections clearly for self studying The majority on quizzes and exams will be covered in the class 5/7/2019 COP4610

Textbook - continued Some comments on the textbook This class focuses on basic principles All the programming assignments will be done in Unix / Linux environment Comments from amazon.com 5/7/2019 COP4610

Programming Environment linprog consists of four linux machines program consists of four Sun workstations Three programming assignments must be done on either linprog or program Doing the assignments on other machines is not allowed 5/7/2019 COP4610

Programming Environment – cont. Access ssh to those machines ssh linprog ssh program 5/7/2019 COP4610

Linux/Unix Tutorial You are expected to know how to use Linux/Unix How to edit a program – e.g., emacs, pico, vi How to compile a program – gcc, g++ How to run a program How to navigate through your files – cd, mkdir, mv, rm, rmdir, ls On-line resources Unix Guide 5/7/2019 COP4610

Expectations You are expected to have a strong desire to learn something new (and may be difficult sometimes) You are expected to be an Operating System expert You are expected to know how to read and understand manuals System calls Unix commands 5/7/2019 COP4610

Expectations – cont. System call manual pages Syntax Semantics Function prototype How to call a function Semantics The meanings of the function What it does with different parameter values fork example 5/7/2019 COP4610

System Overview A computer system consists of hardware and software that are combined to provide a tool to solve specific problems Hardware includes CPU, memory, disks, printers, screen, keyboard, mouse ... Software includes System software A general environment to create specific applications Application software A tool to solve a specific problem 5/7/2019 COP4610

System Overview – cont. 5/7/2019 COP4610

Hardware Resources Processor: execute instructions Memory: store programs and data Input/output (I/O)controllers: transfer to and from devices Disk devices: long-term storage Other devices: conversion between internal and external data representations 5/7/2019 COP4610

Hardware Resources – cont. 5/7/2019 COP4610

Hardware Interface – cont. Everything that a programmer needs to know in order to write programs that perform desired operation on the hardware Disk drive is an example Disk interface provides functions to move disk head, transfer data Monitor Monitor interface provides functions to move the cursor, display characters/graphics 5/7/2019 COP4610

Software Classification System software Provides a general programming environment in which programmers can create specific applications Application software Intended to solve a specific problem 5/7/2019 COP4610

Software Classification - continued 5/7/2019 COP4610

What is an Operating System? The operating system is the part of the system software that manages the use of the hardware used by other system software and all application software It is the system program that acts between the hardware and the user programs 5/7/2019 COP4610

What is an Operating System? - continued It provides services to user programs Through system calls / message passing File system services Memory services I/O services It hides hardware from user programs When your program shows a message on the monitor, it does not need to know the details When your program generates a new file, it does not need to where the free space is on your hard drive 5/7/2019 COP4610

Differences between OS and System Software Major differences between OS and general system software General system software relies on the abstractions provided by OS OS abstracts the hardware directly OS provides the fundamental trusted mechanisms for resource sharing A general purpose OS is domain-independent 5/7/2019 COP4610

Operating System Functions Resource manager manage hardware and software resources Resource abstraction and sharing A nicer environment implement a virtual machine for processes to run in A program in execution is called a process a nicer environment than the bare hardware 5/7/2019 COP4610

Resource Management Functions Transform physical resources to logical resources Resource abstraction Make the hardware resources easier to use Multiplex one physical resource to several logical resources Create multiple, logical copies of resources Schedule physical and logical resources Decide who gets to use the resources 5/7/2019 COP4610

Resource Abstraction Provides an abstract model of the operation of hardware components Like data abstraction in Object-Oriented programming Interface functions Internal functions and status 5/7/2019 COP4610

A Disk Device Abstraction Three interface functions Load(block, length, device) seek(device, track) out(device, sector) 5/7/2019 COP4610

A Disk Device Abstraction – cont. An abstract function for writing 5/7/2019 COP4610

Resource Abstraction – cont. Multi-level abstractions Disk controller -> disk driver -> file system 5/7/2019 COP4610

Resource Sharing Two types of sharing Time multiplexed sharing time-sharing schedule a serially-reusable resource among several users Space multiplexed sharing space-sharing divide a multiple-use resource up among several users 5/7/2019 COP4610

Time-multiplexing the Processor - Called multiprogramming 5/7/2019 COP4610

Time-multiplexing the Processor – cont. - Resulted in concurrent execution or concurrency 5/7/2019 COP4610

Time-multiplexing the Processor – cont. - Multiprogramming can improve the overall system performance 5/7/2019 COP4610

Space-multiplexing Memory 5/7/2019 COP4610

Time-multiplexing I/O Devices 5/7/2019 COP4610

Space-multiplexing the Disk 5/7/2019 COP4610

Issues in Resource Sharing Resource isolation and sharing Protection Sharing Resource allocation Scheduling 5/7/2019 COP4610

Survey This survey consists of a few questions The purpose is to give me a better knowledge of your background so that I may do a better job It will be used as evidence for attendance It will not be used for any grading We will have the first recitation this week This Wednesday, Aug. 27, 2001 5/7/2019 COP4610