PlatformTech.pdf

PLATFORM TECHNOLOGIES Process Management – A process is a program in execution, comprising the executable Chapter 1: Introduction to Operating code, data, stack, program counter, CPU Systems...

PLATFORM TECHNOLOGIES Process Management – A process is a program in execution, comprising the executable Chapter 1: Introduction to Operating code, data, stack, program counter, CPU Systems registers, and open file details. Operating System - Basic set of instructions File Management – Files are used for long- (kernel) that controls the computer's hardware term storage and can be accessed for both input and provides the foundation for other programs and output. to run. Command Interpreter – Provides a Types of Operating Systems: command-line interface, allowing users to interact with the operating system by entering 1. Windows 11 commands at a prompt which it interprets and 2. Ubuntu translates into actions for the operating system 3. Oracle Solaris to execute. 4. iOS 5. Red Hat BASH (UBUNTU) 6. Android 7. Chrome OS ZSH (MACOS) 8. Mac OS CMD (WINDOWS) 9. Windows Server 2022 10. Kali Bourne Again Shell (BASH) – Bash is a Unix 11. Harmony OS shell and command language that serves as the default shell on many Unix-like operating systems. It Server Operating System – Specialized OS is an enhanced version of the original Bourne Shell designed for servers. (sh), incorporating features from the C shell (csh) and Korn shell (ksh). 1. Oracle Solaris 2. Ubuntu Z Shell (ZSH) – Zsh is an advanced Unix shell similar to bash with enhanced user experience with 3. Windows Server features such as improved autocompletion. better 4. Red Hat customization, and additional scripting capabilities. It became the default shell on macOS starting with Client Operating System – Runs on desktop Catalina. computers, laptops, tablets, smartphones, smart watches, and other end-user devices. Command Prompt (CMD) – CMD is a command-line shell and interpreter for the Windows 1. Windows 11 operating system. It provides a text-based interface 2. Android for users to interact with the system, execute 3. Kali commands, run batch scripts, and perform various 4. Harmony OS administrative tasks. 5. Chrome OS 6. iOS System Calls – Allow user-level applications to request services from the kernel. Types of User Interfaces: Signals – Used to notify a process that a Command Line Interface – Allows users to specific event has occurred, like program interact with an operating system by typing completions, or errors. commands into a terminal or console window. Synchronous – These signals occur in Graphical User Interface – Allows users to response to specific actions or conditions interact with an operating system through within the process that are predictable. Asynchronous – These signals occur graphical elements like windows, scrollbars, independently of the process's current buttons, and icons. execution flow and are often triggered by external events or conditions. Functions of an OS: Default Handlers – These are predefined 1. Process Management procedures provided by the operating 2. File Management system for handling specific types of signals. User-Defined Handlers – These are 3. Command Interpreter custom procedures written by developers to 4. System Calls handle signals in a specific manner. 5. Signals 6. Network Management 7. Security Management 8. I/O Device Management 9. Secondary Storage Management 10. Main Memory Management Signal Handling Examples: Famous Client Operating Systems SIGINT Interrupt Windows – Windows is a proprietary operating Signal Type: Asynchronous system developed by Microsoft. It is known for Custom Handling: Yes its graphical user interface (GUI) and extensive Default Handling: Terminates the process. support for a wide range of applications and May be generated by: Pressing CTRL+C hardware. Example of User-Defined Handling: A server application might catch SIGINT to gracefully shut down, closing network connections Linux – An open-source operating system and saving the state before terminating. kernel that, when combined with various distributions (distros), forms complete operating SIGFPE systems. It is known for its stability, security, and Terminate flexibility. Signal Type: Asynchronous Custom Handling: Yes MacOS – Developed by Apple for its Mac Default Handling: Terminates the process gracefully. computers. It is known for its sleek design, ease May be generated by: Clicking the X button on a of use, and integration with other Apple window Example of User-Defined Handling: A products. database application might catch SIGTERM to finish current transactions, close files, and release Android – An open-source operating system resources before shutting down. for mobile devices, developed by Google. It is known for its flexibility, extensive customization SIGKILL options, and wide range of hardware Kill compatibility. Signal Type: Asynchronous Custom Handling: No, IOS – The proprietary operating system Default Handling: Immediately and forcefully developed by Apple for its iPhone, iPad, and terminates the process without any cleanup. iPod Touch devices. It is known for its smooth May be generated by: Clicking "End Task" in task performance, security, and integration with the manager Example of User-Defined Handling: Not Apple ecosystem. applicable, as SIGKILL cannot be caught or ignored by the process. Network Management – Involves monitoring and maintaining computer network connections to ensure they run smoothly and efficiently. Security Management – Ensures that only authorized programs and users can access certain resources like files. memory, and hardware. I/O Device Management – Handles the interaction between the computer and its peripheral devices (like printers, keyboards, and disk drives). Secondary Storage Management – Able to manage secondary storages to store long-term data. Main Memory Management – Operating Systems are also able to manage the main memory for temporary but significantly faster data access. Main memory, or RAM, is a fast but temporary storage area used by the computer to hold data and programs that are currently in use. Chapter 2: Different File Systems Partitions – Logical division of a storage device, like a hard disk drive (HDD) or solid- File System – Manages where data is stored state drive (SSD), that the operating system on the disk and keeps track of where each piece (OS) treats as a separate unit. of information is located. Oo Formatting – Process of preparing a storage Disk Driver – A hardware component that device, like a hard disk drive (HDD) or solid stores digital data on a physical medium, such state drive (SSD), for data storage by setting up as a hard disk drive (HDD) or solid-state drive a file system. (SSD). Types of Formatting: Hard Disk Drive (HDD) – Utilizes magnetism 1. Quick Format – Creates the file system to store data. When accessing data, the disk structure and marks the drive as empty, rotates to the specific location where the essentially resetting the allocation table information is recorded, and the magnetic head without altering the data stored on the drive. detects the magnetic fields to read the data. 2. Full Format – A full format not only sets up Platter – is a circular disk coated with a the file system but also checks the entire magnetic material where data is stored. disk for bad sectors and write zeros to every sector, effectively erasing all existing data. Structure of a Platter: Sectors. Sectors are the smallest physical Directories – also known as a folder, is a data storage units on a hard disk. structure on a disk drive that is used to organize Clusters. (or allocation unit) is a group of and manage files and other directories. contiguous sectors that the file system treats as a Subdirectories are directories that exist within single unit. Tracks. Tracks are concentric circles on the another directory. surface of a single platter where data is written. y Cylinder. A cylinder is a vertical set of all tracks File – A collection of data organized in a across multiple platters that are aligned at the structured manner, assigned a name, and same position. stored on a storage device. Files are accessed using their filename and the Spindle – Primary functions are to rotate directory path where they are located. the platters during read/write operations and For example: D:\Sample Folder\file.txt. to ensure they are properly aligned and spaced from each other. Metadata – Data that describes other data. Read/Write Arm – Responsible for positioning the read/write head over specific Types of File Systems: sectors on the platter. NTFS (New Technology File System) – is Actuator – responsible for positioning the the file system used by Windows NT-based read/write arm based on instructions for operating systems, starting with Windows NT reading or writing data on the platter. 3.1 in 1993 and continuing through Windows 11. Introduced: 1993 Solid State Drive (SSD) – Uses NAND flash Max Volume Size: 256 TB memory chips, where memory cells store data Max File Size: 256 TB as electrical charges. Supports large files and volumes, file permissions, encryption, compression, and journaling. NAND Flash Memory – type of non- Default file system for Windows operating systems. volatile memory used in SSDs, where data is stored in memory cells organized into pages APFS (Apple File System) – is Apple's file and blocks. It retains data even without system introduced in macOS 10.13 (High Sierra) power, with different types (SLC, MLC, TLC) in 2017, optimized for SSDs and other flash offering various balances between storage. performance, endurance, and cost. Introduced: 2017 Types of NAND Flash Memory: Max Volume Size: 8 E3 Max File Size: 8 EB Optimized for SSDs, supports encryption, space 1. SLC (Single-Level Cell) – Each SLC sharing, and snapshots. storage unit holds 1 bit of data per cell. Default file system for macOS 10.13 and later. This configuration provides the highest performance, reliability, and longevity due to the simplicity of storing a single bit. Ext4 (Fourth Extended File System) – is a widely used file system in Linux, introduced in 2. MLC (Multi-Level Cell) – Each MLC 2003 as the successor to Ext3. storage unit holds 2 bits of data per cell. This balance between cost and performance makes MLC suitable for a wide range of Introduced: 2008 Max Volume Size: 1 EB consumer applications. Max File Size: 16 TB Improved performance, supports journaling, and large 3. TLC (Triple-Level Cell). Each TLC file sizes. storage unit stores 3 bits of data. This Common in Linux distributions. configuration allows for greater storage density but results in lower performance and a shorter lifespan compared to SLC and MLC.