Operating system
Operating system（简称OS）是一个非常宏大的主题，涉及的内容非常多。作为一名software engineer，掌握operating system的基础知识是必须的。本节是对OS的概述，参考的是维基百科Operating system。
wikipedia Operating system
An operating system (OS) is system software that manages computer hardware and software resources and provides common services for computer programs.
Types of operating systems
NOTE: 下面罗列了多种分类方法，每种分类方法其实可以看做是一种**特性**。显然有很多的operating system可以兼具多种特性，比如linux，它具备multi-tasking、 multi-user等特性
Single-tasking and multi-tasking
- single-tasking operating system
- multi-tasking operating system
Single- and multi-user
- single-user operating system
- multi-user operating system
Distributed
Templated
Embedded
Real-time
Examples
Unix and Unix-like operating systems
Main article: Unix
Unix interoperability was sought by establishing the POSIX standard. The POSIX standard can be applied to any operating system, although it was originally created for various Unix variants.
BSD and its descendants
Main article: Berkeley Software Distribution
macOS
Main article: macOS
Linux
Main articles: Linux and Linux kernel
The Linux kernel is used in some popular distributions, such as Red Hat, Debian, Ubuntu, Linux Mint and Google's Android, Chrome OS, and Chromium OS.
Microsoft Windows
Main article: Microsoft Windows
Components
The components of an operating system all exist in order to make the different parts of a computer work together. All user software needs to go through the operating system in order to use any of the hardware, whether it be as simple as a mouse or keyboard or as complex as an Internet component.
Kernel
NOTE: 最核心的部分
A kernel connects the application software to the hardware of a computer.
Main article: Kernel (computing)
| Main article | |
|---|---|
| Program execution | Process (computing) |
| Interrupts | Interrupt |
| Modes | User mode and Supervisor mode |
| Memory management | Memory management |
| Virtual memory | Virtual memory Page fault |
| Multitasking | Computer multitasking Process management (computing) Context switch Preemptive multitasking Cooperative multitasking |
| Disk access and file systems | Virtual file system |
| Device drivers | Device driver |
Networking
Main article: Computer network
Security
Main article: Computer security
User interface
Main article: Operating system user interface
Concrete OS structure
本节的标题是“具体的OS的结构":
上面是维基百科 Operating system 所总结的OS的内容。
wikipedia Diversity of operating systems and portability
wikipedia Market share
NOTE: OS的市场份额
Further information: Usage share of operating systems