#ifdef WIN32
# include <win32thread.h>
-#else
-#ifdef NETWARE
+#elif defined(NETWARE)
# include <nw5thread.h>
#else
# ifdef OLD_PTHREADS_API /* Here be dragons. */
# define pthread_mutexattr_default NULL
# define pthread_condattr_default NULL
# endif
-#endif /* NETWARE */
#endif
#ifndef PTHREAD_CREATE
#ifndef YIELD
# ifdef SCHED_YIELD
# define YIELD SCHED_YIELD
-# else
-# ifdef HAS_SCHED_YIELD
-# define YIELD sched_yield()
-# else
-# ifdef HAS_PTHREAD_YIELD
+# elif defined(HAS_SCHED_YIELD)
+# define YIELD sched_yield()
+# elif defined(HAS_PTHREAD_YIELD)
/* pthread_yield(NULL) platforms are expected
* to have #defined YIELD for themselves. */
-# define YIELD pthread_yield()
-# endif
-# endif
+# define YIELD pthread_yield()
# endif
#endif