How to zip a folder from PHP

[tamnm]

I have a folder with structure like this

system/
|__ temp1/
|__ temp2/
|__ test.html
|__ ...

I would like to create system.zip (or system.rar or system.gz) but how I can do it? thanks...

[so_is_this]

exec

(PHP 3, PHP 4, PHP 5)

exec -- Execute an external program

Description

string exec ( string command [, array &output [, int &return_var]] )

exec() executes the given command.

http://us2.php.net/manual/en/function.exec.php