Is it possible (without violating any licenses) to write a native C/C++ application on top of the Android OS and make it run as a daemon process?

There are already several daemon process' running which one can see with the 'ps' command, the legal part concerns me the most. And also the lack of documentation on how to exactly do this.

For the writing part, I guess one could use basic Linux programming concepts, since Android supports at least to some level the standard Posix API. To make it run as the phone boots, some modifications is of course required in init as well.

I have no plans to have this app in the Android Market, so installing it manually to the phone is not a problem. As long as it does not require re-compiling the whole OS or kernel.

I really appreciate all info on this topic, since there's isn't much available.

Thanks.