Depending on your needs, you might be able to use a proxy node like
rosbridge ( http://www.ros.org/wiki/rosbridge ). All your embedded
environment would need to support would be a socket library and
(optionally) a JSON library. The throttling capabilities of rosbridge
are especially useful if processing power is at a premium.

I'm obviously more than a bit bias, but I've found writing pure-C
clients, especially special purpose clients that just listen or
publish to one message type, pretty easy to write.

_Trevor