http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54847
--- Comment #45 from Jack Howarth <howarth at nitro dot med.uc.edu> 2012-10-08 22:27:08 UTC --- I can confirm the existence of sched_yield() back to Libc-166 in 1997 on darwin. http://opensource.apple.com/source/Libc/Libc-166/pthreads.subproj/sched.h The nanosleep() call appears at least by Libc-262.2.12 in 2003 on darwin... http://opensource.apple.com/source/Libc/Libc-262.2.12/include/time.h and probably goes back further but the archived Libc don't show the time.h header before then.
