--- ./usr/include/semaphore.h.orig
+++ ./usr/include/semaphore.h
@@ -71,9 +71,14 @@
 int sem_trywait(sem_t* __sem);
 int sem_wait(sem_t* __sem);
 
-/* These aren't actually implemented. */
+#undef sem_open
+#define sem_open libandroid_sem_open
 sem_t* sem_open(const char* __name, int _flags, ...);
+#undef sem_close
+#define sem_close libandroid_sem_close
 int sem_close(sem_t* __sem);
+#undef sem_unlink
+#define sem_unlink libandroid_sem_unlink
 int sem_unlink(const char* __name);
 
 __END_DECLS
