Linux notes-Operating system basics

• System work

Applications (direct programming of system hardware, high efficiency of application operation)

Hardware--Kernel (kernel) applications

| Library Call API Interface

| Shell (graphical interface or text window)

Coordinate, allocate hardware resources and monitor

• Application startup process

Keyboard, mouse or command input--CPU--Kernel (kernel)--Application

• Shell

: interface, interface, inter-machine interaction

GUI: Graphical user interface with KDE application. Gnome. XFACE

CLI: command-line interface, command prompt (prompt) # (root admin) ￥ (normal user), app has bash,csh.zsh.ksh.tcsh where bash app is the most extensive and the default shell

• Kernel features

1. Process Management 2. Memory Management 3. File System 4. Network system 5. Hardware System 6. Security mechanism

• Basic principles of Linux

1. A small program consisting of a single purpose, combined with a small program to complete complex tasks

2. All documents, including drives, hard drives, optical drives, are in the form of a file

3. Avoid capturing user interfaces as much as possible

4. Configuration files are saved in text format

• Command format

Command (or executable) option parameter (can also have multiple parameters)

Command: Must be an instruction or executable file

Options: Correcting how commands are executed

Short option:-L (letter) can also use multiple letters at the same time-ali

Long option:--time (word) but cannot use multiple words at the same time

Arguments: The object that the command acts on, can have several objects, and the objects are separated by spaces

• User interface

In the text window, there are 6 interfaces that can be switched via: Ctrl + ALT + F1-F6 (terminal), and there is a terminal in the system options in the graphical interface--analog terminal

• User's Switchover

Su:switch User

Su-l user name This is a full switch

SU user name This is a half switch

• Password complexity rules

1. Use at least 3 kinds of 4 kinds of characters wrongly written characters

2. Long enough, greater than 7 bits

3. Using Random strings

4. Regular password change, usually 2 months

5. Long cycle times for password strings

This article is from the "stupid Bird first-FAI" blog, please be sure to keep this source http://benniaoxianhui.blog.51cto.com/10463960/1670351

Linux notes-Operating system basics