ITRON probably has a lot more installs than all these OSes, although I don't think it's very popular in the US. http://en.wikipedia.org/wiki/TRON_Project http:

ITRON probably has a lot more installs than all these OSes, although I don't think it's very popular in the US. http://en.wikipedia.org/wiki/TRON_Project http://en.wikipedia.org/wiki/TRON_Project http://www.t-engine.org/tron-project/itron http://www.t-engine.org/tron-project/itron (with source code)