diff --git a/libguile/ioext.c b/libguile/ioext.c
index dddd38dda..6d57cd3ee 100644
--- a/libguile/ioext.c
+++ b/libguile/ioext.c
@@ -55,6 +55,9 @@
 
 #include <fcntl.h>
 
+#ifdef HAVE_IO_H
+#include <io.h>
+#endif
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
diff --git a/libguile/ports.c b/libguile/ports.c
index 9e1acad54..7a02b1308 100644
--- a/libguile/ports.c
+++ b/libguile/ports.c
@@ -67,6 +67,10 @@
 #include <malloc.h>
 #endif
 
+#ifdef HAVE_IO_H
+#include <io.h>
+#endif
+
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif