PHP eding another PHP file

Hi. me and my friends are working on a text based rpg game. what i need is to have PHP to go and edit a file that contains a huge PHP file like below

Example:
<?php
$color1 = red;
$color2 = blue;
$color3 = green;
?>


Pages like these are going to be included in other files to set variables. But as the player advances through the game these variables will change. I need a PHP to get this file, find a specific variable, such as $color2, and edit it.

For example, if i have $money = 100; in that file and the player earns $10, I need PHP to find $money and add 10 to it.
How can I do this.
Also, the game is in early development and I will plan on using SQL. But not now...

Thank You!

You will save yourself a lot of coding if you do it in sql right now...

If you insist on doing it this way, write a php library with basic functions like "set_color" and "get_color" so that when you shift this to mysql all you need to do is change the insides of those definitions - you don't have to change code in more than one file.

As for what you're trying to do now, I'd suggest using fseek and fgets

http://us2.php.net/manual/en/function.fgets.php
http://us2.php.net/manual/en/function.fseek.php

so if i use this code:
<?php

$fp = fopen('somefile.txt', 'r');

// read some data
$data = fgets($fp, 4096);

?>


how do i have the script select a spicific variable. then what would i do to have it edit it
and what is the 4096 for?
thanks