Shell Programming

Shell Introduction

Shell is a program written in C language, it is a bridge for users to use Linux. Shell is both a command language and a programming language.

Shell Script

The industry usually refers to Shell Script, but Shell and Shell Script are two different concepts.

First Shell Script

Creation a file named feige.sh

#!/bin/bash
echo "Hello World !"

Execute Script

sh ./feige.sh

Shell Variable

Output System Variable

echo $PATH
echo $USER