On Aug 11, 2014, at 8:08 AM, Joel Sherrill <joel.sherrill@OARcorp.com> wrote: > +#if defined(__rtems__) > +#include <unistd.h> > +/* Required, for read(), write(), and close() */ > +#endif Strikes me as exceptionally odd. Should be done unconditionally, and any system that doesn’t like that should be the odd ball.