diff --git a/libc/include/sys/sysconf.h b/libc/include/sys/sysconf.h
index 2fc1b08..0a46e7a 100644
--- a/libc/include/sys/sysconf.h
+++ b/libc/include/sys/sysconf.h
@@ -127,8 +127,9 @@
 #define _SC_NPROCESSORS_ONLN            0x0061
 #define _SC_PHYS_PAGES                  0x0062
 #define _SC_AVPHYS_PAGES                0x0063
+#define _SC_MONOTONIC_CLOCK             0x0064
 
-extern int sysconf (int  name);
+extern int sysconf(int name);
 
 __END_DECLS