Shellscripts with variables

Learning outcomes:

Use a script to demonstrate the use of a positional parameter
Show how to get user input for a script using read
Explain the use of set with backticks

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Shell Scripting with inputs and variables

Variables

Variables in Linux are untyped
Any word (that isn't reserved) can be a variable
Use $ to use variable

Small script asking for name and then saying hello, try out the code below yourself!
Example:

                    #!/bin/bash

                    Echo "What's your name?"
                    
                    Read name
                    
                    Echo "Hello $name"

Positional parameters

Used to pass info to a script when executed instead of using an input method such as "read"
Numbered starting at 1 with some special parameters (such as $* and $? to get all or some of the contents of the temp variables)
Example to put Jane as $1:
```
                    ./testscript.sh Jane
```
echo "hello $1" #should say hello Jane
Example to put Jane as $1 and Doe $2
```
                    ./testscript.sh Jane Doe
```
echo "hello $1 $2" # should say hello Jane Doe

Positional parameters and backticks

use set `date` (backticks not single quote) Puts the results in positional parameters, an example can be found here
An example of the set command
Set command in shell scripting
Set - $VARIABLE” in bash

Suggested Activities and Discussion Topics:

Watch this video and follow along to create a shell script.

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