Stiring variables

[eduinfo]

Hi,
i would like to do this.
Suppose there is a file named
config.inc.php
with contents

<?php
$abc="value";
?>

The n i use this file in another file

<?php 
require("config.inc.php");

perform calculations on $abc;
Store value of $abc on config.inc.php
?>

Just tell me ghow can i store the new value of the variable $abc in config.inc.php so that any subsequent call to the file uses newer values everytime.
I basically want to keep the work done by one instance of a script so that the next instance can use it.
I know i may store values in a mysql database or evn by using file handling functions.
But this invlolves overheads!
Is there a more efficient implementation?
will be very greatful for a reply

[GBahle]

You wont be able to avoid using file access to update the variable. The standard way to do sth like this is write a new file, with everything but the line(s) to change in it, insert the new stuff at the right spot (while writing), save it under a new name, delete the old file and rename the new one.

Using a database for that kind of stuff is highly recommended.

If you understand German, this may be helpful

http://www.dclp-faq.de/ch/ch-open_exec.html