CMPSC 311 - Introduction to Systems Programming

Flashcards about CMPSC 311 Lecture Notes

Multiuser

Supports multiple users on the system at the same time, each working with their own terminal.

Multitasking

Supports multiple programs at a time.

Portability

When moving from hardware to hardware, only the lowest layers of the software need to be reimplemented.

GNU (GNU is Not UNIX)

Free software project started by Richard Stallman in 1983, which includes gcc, gdb, bash, and emacs.

Linux

An operating system kernel developed by Linus Torvalds.

OS Kernel

Direct interaction with hardware/firmware

System Calls

Interface to the kernel

System Libraries

Wrappers around system calls

Programming Language Libraries

Extends system libraries

System Utilities

Application-independent tools.

Command Interpreter/Command Shell

User interface (in terminal program).

Application Libraries

Application-specific tools.

Applications

Complete programs for ordinary users.

Open Source Software

Distributed with a license where the copyright allows the user of the source to review, modify, and distribute with no cost to anyone.

Operating System

Software that directly interacts with the hardware, manages hardware resources, and abstracts away messy hardware devices.

OS as Abstraction Provider

A module that a program can call (with system calls) and provides a powerful API (the POSIX API).

Privilege Mode

Hardware state that restricts the operations that code may perform.

User Mode

Used for normal programs running with low privilege.

Kernel Mode

The operating system running with high privilege.

Device Driver

Software module that implements the interface to a piece of real or virtual hardware.

Kernel Modules (Loadable Kernel Modules)

Software modules that run in kernel space that can be loaded (and unloaded) on a running system, extending the kernel functionality without recompilation.