Primary and Secondary Usergroup permission interaction

[ErnestA]

Hi, I've been researching usergroup permissions and how multiple groups interact with each other. From what I've read it seems like permissions are added "bitwise". For example, if a user has access to a mod in their primary group, but does not have access to it in any of their secondary groups, they will still gain access to the mod as long as at least ONE of their groups have access.

I.E. 001+000+000 = 001.

The mod is using $permissions and $vbulletin->bf_ugp.

The author is trying to tell me that if a user is a member of 3 groups, that all three groups have to have access permissions set for the mod or the user will be denied access. This seems like a load of bunk to me... Seems more like a coding error to me.

I just want to confirm how permissions are supposed to behave before I communicate back to them.

Thanks,

ErnestA.