Communication Between Objects

Within the project I'm working on, I need two objects to send messages to each other. The objects are completely separate from each other, and I need the dialogue between them to be invisible to players. I've tried whisper with no luck, but I may just be using it incorrectly. Anyone know a good way to have an object send a message to another?

llWhisper (or llRegionSay if your objects are located in the same sim so that can work) with a listen would usually be the simplest way to do it. Can you post an example of a chat/listen combination that isn't working for you?

One very common problem: make sure that your listen and chat are tuned into the same channel!

llEmail would also work well here.

As a side note to this, odds are good that in the cases where you can use llEmail between objects, the new HTTP-in feature would be a better choice; faster and with easier back-and-forth communication.
Both are a little trickier to use than a (region)say, because they require knowledge of a predetermined address (in the email version, based on the prim's key, and in the HTTP-version, based on an even more indirect address).

Hmm looks like I was just making a very silly mistake. Everything is working fine now with llSay and llListen. Thanks for the responses, everyone .

just ignore me if I am being too simple here.... if you have the objects say and listen on a channel other than 0, then avatars would have a hard time discovering the channel.... use something in the high negative range (or is that low?) like -93647816

Yes, but the heart of the OP's question was about how to communicate over a distance, not just about how to do it privately. That's why the thread turned to comparisons of llSay, llRegionSay, llEmail, and the new HTTP commands.