Systems Programming Overview

Flashcards covering the fundamentals of systems programming, software categories, operating system architecture, Linux, and memory manipulation in C.

System

A collection of various components.

Programming

The activity of designing and implementing programs.

Systems Programming

The activity of designing and implementing system programs required for the effective execution of general user programs on a computer system.

Utilities

Small programs or tools designed to perform specific tasks that help manage, maintain, or support system functionality.

Disk Cleanup (Windows)

A utility that frees disk space by removing unnecessary files.

Task Manager (Windows)

A utility used to monitor and manage running processes and system performance.

Terminal (Unix/Linux)

A command-line interface for interacting with the operating system, also known as $cmd.exe$ in Windows environments.

Antivirus Programs

Security software, such as Norton or McAfee, designed to protect the system from malware and viruses.

Firewall Software

Software like Windows Firewall that monitors and controls incoming and outgoing network traffic.

Control Panel (Windows)

A tool that provides access to system settings and configurations.

System Preferences (macOS)

A configuration tool that allows users to adjust system settings on Mac computers.

Application Software

A program or set of programs used to solve a problem using the computer as an instrument, such as word processors, web browsers, or media players.

System Software

Software that supports the operation of the computer by interfacing between the hardware and application software, including compilers, assemblers, and operating systems.

Operating System (OS)

A special program that resides between the computer hardware and application software.

Linux

A multiuser, multitasking, free, and open-source operating system with a Unix-like feel.

Linux Distribution

A package consisting of the Linux kernel, basic software, utilities, and a software package manager; examples include Debian, Fedora, Gentoo, and Kali.

Kernel

The central part of the Operating System that interfaces directly with the hardware.

Shell

The user interface used for command execution in an operating system.

System Calls

The interface between a running program and the operating system, generally available as assembly-language instructions or through high-level languages like C.

GNU C Library (glibc)

A library that provides wrappers for system calls, support for threading, and basic application services for Linux.

CPU Usage

The percentage of CPU time spent on non-idle tasks.

User Mode

A restricted CPU mode where specific instructions, such as modifying page tables, are prohibited.

Kernel Mode

A privileged CPU mode where the OS has super-privileges and control over the hardware.

errno

A specific variable used to store an error number when a system call fails and returns $-1$.

Bitwise Operators

Tools introduced by the C language for manipulating memory at the bit level on integral types, including AND ( & ), OR ($|$), XOR ( ^ ), and NOT ($~$).

$$memcpy$$

A memory manipulation function that copies a block of $n$ bytes from a source to a destination.

$$memset$$

A memory manipulation function that sets $n$ bytes of a memory block $s$ to a specific byte value $c$.

$$memcmp$$

A memory manipulation function that compares the first $n$ bytes of two arrays, specifically $s1$ and $s2$.