命令行用法查询

cheat

1、安装

Ubuntu
$ sudo apt install python3 python3-pip 
$ pip install cheat

Centos
$ yum install python python-pip 
$ pip install cheat

2、使用
$ cheat  tar

$ cheat -l  //查询哪些命令

Tldr++

https://github.com/isacikgoz/tldr

tldr tar