micropython/micropython — pull request #471 by errordeveloper (2014-04-12 19:12:07+00:00)
Title: py: the entire `<unistd.h>` shouldn't be needed

Chaning this worked for me with AMRCC and their libc, but I'm not too sure whether `` is the lowest common denominator.
Potentially we could put a check around what compiler we are using, but looks like there is nothing specific in `` that these files currently require.