diff --git a/binaries/opae.io/main.h b/binaries/opae.io/main.h
index 2ef003320079..1860421dc635 100644
--- a/binaries/opae.io/main.h
+++ b/binaries/opae.io/main.h
@@ -27,6 +27,7 @@
 #pragma once
 
 #include <iostream>
+#include <unistd.h>
 #include <sys/ioctl.h>
 #include <opae/vfio.h>