Picked from include/paths.h.
See more http://www.openwall.com/lists/musl/2014/03/29/5

diff --git a/hyptop/helper.c b/hyptop/helper.c
index 1212bda..733fd4e 100644
--- a/hyptop/helper.c
+++ b/hyptop/helper.c
@@ -27,6 +27,7 @@
 #include "hyptop.h"
 #include "sd.h"
 
+#define	_PATH_MOUNTED	"/etc/mtab"
 /*
  * Globals
  */
