Operating Systems: Chapter 1

Trap

A software-generated interrupt caused either by an error or a user request.

Interrupt Driven

An operating system is (blank).

Computer System Structure

1) Hardware 2) Operating System 3) Application Programs 4) Users

Components of a Computer System

1) Users 2) System and Application Programs (i.e. compiler, assembler, text editor, database system, etc.) 3) Operating System 4) Computer Hardware

Buffer

A buffer is a region of memory used to temporarily hold data while it is being moved from one place to another. (Think of it as a trash dump.)

Operating System

A collection of software that manages computer hardware resources and provides common services for computer programs. - Execute user programs and make solving user problems easier - Make the computer system convenient to use - Use the computer hardware in an efficient manner It is a resource allocator that manages all resources and decides between conflicting requests for efficient and fair resource use. It is also a control program. It controls the execution of programs to prevent errors and improper use of the computer.

Compiler

A compiler searches all the errors of a program and lists them. If the program is error free then it converts the code of program into machine code and then the program can be executed by separate commands.

Application Program Interface

A set of routines, protocols, and tools for building software applications. An API specifies how software components should interact and APIs are used when programming graphical user interface (GUI) components.

BUS

A set of wires of lines that connects various components inside a computer.

Interrupt

A signal to the processor emitted by hardware or software indicating an event that needs immediate attention. An interrupt alerts the processor to a high-priority condition requiring the interruption of the current code the processor is executing.

Registers

A special, high-speed storage area within the CPU. All data must be represented in a register before it can be processed. For example, if two numbers are to be multiplied, both numbers must be in registers, and the result is also placed in a register. (The register can contain the address of a memory location where data is stored rather than the actual data itself.)

Shell

A user interface for access to an operating system's services. In general, operating system shells use either a command-line interface (CLI) or graphical user interface (GUI), depending on a computer's role and particular operation.

Interpreter

An interpreter checks the errors of a program statement by statement. After checking one statement, it converts that statement into machine code and then executes that statement. The process continues until the last statement of program occurs.

CSS Operating System

Controls and coordinates use of hardware among various applications and users

Control Program

Controls execution of programs to prevent errors and improper use of the computer.

Input/Output Devices

I/O devices are used by a human (or other system) to communicate with a computer. For instance, a keyboard or mouse is an input device for a computer, while monitors and printers are output devices.

Kernel

It is a computer program that constitutes the central core of a computer's operating system. It has complete control over everything that occurs in the system. As such, it is the first program loaded on startup, and then manages the remainder of the startup, as well as input/output requests from software, translating them into data processing instructions for the central processing unit. It is also responsible for managing memory, and for managing and communicating with computing peripherals, like printers, speakers, etc.

Bootstrap Program

Loaded at power-up or reboot. It is typically stored in ROM or EPROM and it initializes all aspects of the system. It also loads the operating system kernel and starts the execution.

Resource Allocator

Manages resources and decides between conflicting requests for efficient and fair resource use.

CSS Users

People, machines, and other computers

Firmware

Rermanent software programmed into a read-only memory i.e. ROM, EPROM, etc.

Interrupt Vector

The memory location of an interrupt handler, which prioritizes interrupts and saves them in a queue if more than one interrupt is waiting to be handled.

CSS Application Programs

defines the ways in which the system resources are used to solve the computing problems of the users

CSS Hardware

provides basic computing resources CPU, memory, I/O devices