diff --git a/migration-tcp.c b/migration-tcp.c
index df8080f..fefa14e 100644
--- a/migration-tcp.c
+++ b/migration-tcp.c
@@ -262,7 +262,7 @@ MigrationState *tcp_start_outgoing_migration(const char *host_port,
 	return NULL;
     }
 
-    fcntl(s->fd, F_SETFL, O_NONBLOCK);
+    socket_set_nonblock(s->fd);
 
     if (s->detach == 1) {
         dprintf("detaching from monitor\n");