--- arc-5.21m/tmclock.c
+++ arc-5.21m/tmclock.c
@@ -14,7 +14,7 @@
 /* Julian day number of the Unix* clock's origin, 01 Jan 1970. */
 #define JD1970 2440587L
 #define	CENTURY	19
-#if	BSD
+#if	BSD || defined(__MACH_O__)
 #include <sys/time.h>
 #else
 #include <time.h>