How does one gain control over a process that's bout to run?

[xandaz]

    Hey guys. How does one gain control over a process or application that is about to run? How do firewalls do it? Are there any specific functions to achieve this?
    Feel free to reply. I looked around in the forum but found nothing. I'm not sure i know what to search for. I hope this isn't one those trust breaking issues that put me on the forum's black list. If it is then ... many sorries.
   Ty and bye :)

[drizz]

You would write a driver that uses PsSetCreateProcessNotifyRoutine.

Heres an article from microsoft:
http://www.microsoft.com/msj/0199/nerd/nerd0199.aspx

[xandaz]

    Thanks alot drizz. I'm looking into it.
    Ty and bye :)