CSCI 440: Operating Systems

What services does an OS provide

What are the main functions an OS provider

How does one interact with a computer system?

  1. User interface

  2. command line interface

  3. GUI

  4. System calls

What is a system call?

It is a request that a program makes of the kernel, only the kernel has the privilege to do

Usually abstracted by an API

What is an API

Provides an abstraction to numerous system calls to accomplish a task, provides simple methods to programmers to do complex tasks

Types of system calls

  1. Process control: fork, wait, signal
  2. File Management
  3. Device Management
  4. Information management
  5. Communication: IP, Networking

Mechanisms and Policies

Mechanisms determine determine how to do something. Policies determine what will be done

What kind of structure can an OS have

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