diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index a0dbb418..930844a6 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -14,6 +14,7 @@
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/fcntl.h>
+#include <sys/uio.h>
 #include <sys/un.h>
 #include <unistd.h>
 #include <errno.h>