Making scripts executable

Earlier in this module, you wrote the first script and ran it using the sh <file_name> command. Typing sh before the file name every time becomes tedious — that is where making a script executable comes in.

You can make a script executable, meaning the operating system will treat it like a runnable program. Instead of typing sh hello each time, you just type ./hello.

This is done using the chmod u+x <file_name> command, which updates the file's permissions to allow it to be run directly. Think of permissions as a gate — chmod u+x opens the gate for your user account to execute the file.

Consider the previous example

#!/bin/bash

echo "Hello, World"

To make this executable, do:

chmod u+x hello

Then to run it, do:

./hello

You should get the same result as before, but this is more efficient than typing sh hello every time.

As a final example, if our file name is delete_all and we want to make it executable and run it, we can do:

chmod u+x delete_all
./delete_all

That said, we're done here! Over to the next one.