You can pass arguments to your shell script when you execute it. To pass an argument you just need to write it right after the name of your script. For example:
In the script, we can then use
$1 in order to reference the first argument that we specified.
If we pass a second argument it would be available as
$2 and so on.
Let's create a short script called
arguments.sh as an example:
#!/bin/bash echo "Argument one is $1" echo "Argument two is $2" echo "Argument three is $3"
Save the file and make it executable:
chmod +x arguments.sh
Then run the file and pass 3 arguments:
./arguments.sh dog catbird
The output that you would get would be:
Argument one is dog Argument two is cat Argument three is bird
To reference all arguments you can use
#!/bin/bash echo "All arguments: $@"
If you run the script again:
./arguments.sh dog cat bird
You will get the following output:
All arguments: dog cat bird
Another thing that you need to keep in mind is that
$0 is used to reference the script itself.
This is a good way to create self destruct the file if you need to or just get the name of the script.
For example, let's create a script that prints out the name of the file and deletes the file after that:
#!/bin/bash echo "The name of the file is: $0 and it is going to be self-deleted" rm -f $0