Linux operating system

Basic principles of Linux:

1. Consisting of small programs of a single purpose 2. All documents 3. Avoid capturing user interfaces 4. Save the configuration file in text format

Gpl:general public liscense Gnu:gun are not Unix

Gui:graphical user Interface

CLI Interface: Command line interface

Command Prompt Prompt,bash

#:root

$: Normal User

Command format: elf:executable and linkable format

Command options (short option, long option) parameters

Magic number can indicate the format in which the binary program executes

Shared library (Systemcall with kernel underlying): Shared object

Minimum Os:kernel+bash Dependent library +bash

Authentication: Certification

Authorization: Authorization

Audition: Audit log

Directory: Path Mapping file

ls command

-L Long format

File type-Normal file d directory file B block device C character device L Symbolic link p pipe s socket file

File permissions: rwx rwx rwx file hard-link count owner group file Size file timestamp access (Access) modify (content) change (attribute metadata)

Linux operating system