I've always found it useful to be able to run PHP applications from the command line: not only does it allow me to quickly view the output of my code from the command line - where I do the majority of my developing - but it also allows me to make proper command line applications from within PHP. Okay, quite a lot of stuff is not possible, but it's still fun. This applies to Unix only, I believe.

The first way (the old way):

Run this from bash:

php index.php

That's not an application, as it is just telling php to run index.php.

To be able to run it simply by typing the file name, follow these steps:

1. Run whereis php in a terminal and copy what it prints.

2. Add the following code to the top of your php file:

#! /usr/bin/php

/usr/bin/php is what whereis php gave me, replace it with what it gave you. Basically, this is telling the command line the location to PHP, and where to run the application. It is called a hashbang due to the #!.

3. Make the application an application by running the following code in the command line (where index.php is your application):

chmod +x index.php

You can then run your application by running the following:

./index.php

It's that simple!