<> What is? Linux operating system

Linux operating system (GNU/Linux) It is a set of free use and free dissemination classes Unix operating system , Is based on POSIX Multiple users of , Multitask , Support multithreading and multithreading CPU Operating system of .

<> characteristic

* basic thought : Everything is a document ; Each document has a definite purpose
* Completely free
* Fully compatible POSIX1.0 standard
* Multi user , Multitask
* Good interface
* Support multiple platforms
<> advantage

* Linux Composed of many micro cores , Its source code is completely open source , Collect the essence of global programmers
* Inherited Unix Characteristics of , It has very powerful network functions , It supports all Internet protocols , Available Unix Develop a new protocol stack based on the network characteristics of
* Complete system tool chain , Simple operation can configure a suitable development environment , Can simplify the development process , Reduce obstacles to developing simulation tools , So that the system has strong portability .
<>Liunx Directory structure of

root Administrator's home In directory root in ;
Other users' home Catalog home In directory .

<>Linux Common commands

<> redirect output

* > redirect output , Overwrite the original content
eg: cat /etc/password > a.txt Redirect output to a.txt

* >> redirect output , Additional functions
eg: cat /etc/passed >> a.txt Output and append

<> System management commands

ps Status of a running process

ps –ef View all processes
ps –ef | grep ssh Find a process
kill 2868 Kill 2868 Numbered process
kill -9 2868 Force kill process

<> The Conduit

* concept : yes Linux An important concept in command , The function is to use the output of one command as the input of another command .
ls --help | more Paging query help information
ps –ef | grep java Query name contains java Process of
ifconfig | more
cat index.html | more
ps –ef | grep aio

<>Linux Permission command for

<> file right

<>Linux Three file types

* Ordinary documents : Include text files , data file , Executable binary program file ······
* Catalog file :Linux The system treats the directory as a special file , Use it to form the tree structure of the file system .
* Equipment documents :Linux The system treats each device as a file .

©2019-2020 Toolsou All rights reserved,
Solve in servlet The Chinese output in is a question mark C String function and character function in language MySQL management 35 A small coup optimization Java performance —— Concise article Seven sorting algorithms (java code ) use Ansible Batch deployment SSH Password free login to remote host according to excel generate create Build table SQL sentence Spring Source code series ( sixteen )Spring merge BeanDefinition Principle of Virtual machine installation Linux course What are the common exception classes ?