--- a/mfsclient/nbdmain.c	2020-06-08 08:19:08.422379805 +0200
+++ b/mfsclient/nbdmain.c	2020-06-08 08:18:55.079380447 +0200
@@ -39,6 +39,7 @@
 #include <errno.h>
 #include <inttypes.h>
 #include <pthread.h>
+#include <sys/file.h>
 
 #ifdef HAVE_LINUX_NBD_H
 #include <linux/nbd.h>
