Shell Summary of special variables: Location variables $1, $ *, $?

$1 indicates the first parameter. $ * indicates all parameters entered by the user.

The hello1 script is as follows. A location parameter is acceptable.

#! /Bin/bash

Echo $1

 

Run the Script:./hello1 "Hello World" and output Hello World on the screen.

 

The hello2 script is as follows. It cyclically reads all user input parameters and displays them on the screen.

#! /Bin/bash

For VaR in $ *; do

Echo "your input is $ Var"

Done

 

Run the Script:./hello2 Xiaojun yangna screen output:

Your input is Xiaojun

Your input is yangna

 

$? Indicates the return value of the last executed script. If the return value is successful, 0 is returned. If the return value is unsuccessful, 1 ~ is returned ~ Value Between 255