The shell variable definition uses

Shell:

1, local variables: variables available only in the current shell,

2, Environment variables: variables available for the current Shell's child processes

3, Shell variables: some shell Set the special variables, such as: $ $, $ ... These

 

Definitions:

 
   Variable name naming rules: case, underscore 
 
   
 
 using: (with $ symbol) 
 
#!/bin/shname= "Zara Ali" echo $NAME 
 
 
 
 Read-only variable: (readonly keyword) 
 
#!/bin/shname= "Zara Ali" ReadOnly namename= "Qadiri" 
 
   Run the code above will prompt: 
 
/bin/sh:name:this variable is read only. 
 
 
 
 Delete variable: (unset keyword) 
 
 
   Run the above code will not output 
 
   
 
 Shell variable definition using