--- a/defs.h
+++ b/defs.h
@@ -4,6 +4,10 @@
 #ifndef __DEFS_H__
 #define __DEFS_H__
 
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <ctype.h>
 
 
 #ifdef IS_LITTLE_ENDIAN