diff --git a/appl/popper/popper.h b/appl/popper/popper.h
index 56bd19cd1..35369996e 100644
--- a/appl/popper/popper.h
+++ b/appl/popper/popper.h
@@ -41,6 +41,9 @@
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif
+#ifdef HAVE_IO_H
+#include <io.h>
+#endif
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif