Prerequisites for getting started with Shell

1. Create and run Shell programs

What is a shell program? Simply put, a shell program is a file containing several lines of shell or Linux commands.

Like programming in advanced languages, writing a shell program requires a text editor, such as VI.

In the text editing environment, enter shell/Linux Command lines based on Shell syntax rules to form a complete program file.

There are four methods to execute shell program files

(1) # chmod + X file (in/etc/profile, add export path =$ {path }:~ /Yourpath, which can be directly run under the command line, just like executing a common command)

(2) # sh File

(3) #. File

(4) # source file

When writing a shell, the first line must specify the shell that the system needs to explain your shell program, such :#! /Bin/bash ,#! /Bin/CSH,/bin/tcsh, or #! /Bin/pdksh.