diff --git a/Modules/fcntlmodule.c b/Modules/fcntlmodule.c
index d08123a22ad..842e4369d6d 100644
--- a/Modules/fcntlmodule.c
+++ b/Modules/fcntlmodule.c
@@ -42,6 +42,7 @@ PERFORMANCE OF THIS SOFTWARE.
 #include <sys/file.h>
 #endif
 
+#include <sys/ioctl.h>
 #include <fcntl.h>