--- a/ft.h
+++ b/ft.h
@@ -13,15 +13,24 @@
 #ifndef FT_H
 # define FT_H
 
+#include <ctype.h>
+
 //for MacOS, MALLOC_SIZE_FUNCTION Macro should be malloc_size 
 //for Windows, MALLOC_SIZE_FUNCTION Macro should be _msize 
 //for GLIBC systems, MALLOC_SIZE_FUNCTION Macro should be malloc_usable_size
+#ifdef __GNU_LIBRARY__
+#define MALLOC_SIZE_FUNCTION malloc_usable_size
+#else
 #define MALLOC_SIZE_FUNCTION malloc_size
+#endif
 
 //For Windows/GLIBC next #include should be "#include <malloc/malloc.h>" 
 //For MacOs next #include should be #include <malloc.h> 
+#ifdef __GNU_LIBRARY__
+#include <malloc.h>
+#else
 #include <malloc/malloc.h>
-
+#endif
 
 //Includes
 #include <stdio.h>