--- a/util_lib/include/sha256.h
+++ b/util_lib/include/sha256.h
@@ -1,7 +1,8 @@
 #ifndef SHA256_H
 #define SHA256_H
 
-#include <sys/types.h>
+//#include <sys/types.h>
+#include <stddef.h>
 #include <stdint.h>
 
 typedef struct