+#define sys_futex sbcl_sys_futex
+static inline int sys_futex (void *futex, int op, int val, struct timespec *rel)
+{
+ return syscall (SYS_futex, futex, op, val, rel);
+}
+
+int
+futex_wait(int *lock_word, int oldval)
+{
+ int t= sys_futex(lock_word,FUTEX_WAIT,oldval, 0);
+ return t;
+}