diff --git a/io.h b/io.h
index 1f52a21..4736a32 100644
--- a/io.h
+++ b/io.h
@@ -2,6 +2,10 @@
 #ifndef IO_H
 #define IO_H
 
+#ifdef __MINGW32__
+#include_next <io.h>
+#endif
+
 /* http://cr.yp.to/lib/io.html */
 
 #include <libowfat/uint64.h>
diff --git a/io_internal.h b/io_internal.h
index 9b6c0d6..02341e5 100644
--- a/io_internal.h
+++ b/io_internal.h
@@ -6,6 +6,7 @@
 #include "libowfat/array.h"
 #include "libowfat/iarray.h"
 #ifdef __MINGW32__
+#include <winsock2.h>
 #include "socket.h"
 my_extern HANDLE io_comport;
 #else