Define EXIT_SUCCESS and EXIT_FAILURE if necessary

include/ac/stdlib.h

@@ -19,4 +19,9 @@
 #		include <malloc.h>
 #	endif
 
+#	ifndef EXIT_SUCCESS
+#		define EXIT_SUCCESS 0
+#		define EXIT_FAILURE 1
+#	endif
+
 #endif /* _AC_STDLIB_H */