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:

Lab assignment: PDF version (accessible HTML version)
Watch this video and follow along to create a shell script.
Activity: Listen to This Podcast That was created using AI from these materials. Transcript for the Podcast What are your thoughts? Did the AI do a good job representing the materials? Did you find any mistakes?
Go through This AI generated study guide, what do you think? Did it capture the week materials well? How did you do on the self quiz? Do you know all the vocab used?
Go through This AI generated briefing document, what do you think? Did it capture the week materials well? Was there anything it missed? Do you know all the vocab used?

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