diff --git a/monitor/main.c b/monitor/main.c
index d4e8e6d..21b890b 100644
--- a/monitor/main.c
+++ b/monitor/main.c
@@ -96,6 +96,7 @@
 	int exit_status;
 	sigset_t mask;
 
+	setvbuf(stdout, NULL, _IOLBF, 0);
 	mainloop_init();
 
 	filter_mask |= PACKET_FILTER_SHOW_TIME_OFFSET;
diff --git a/src/main.c b/src/main.c
index 15f98cf..7e5bcdb 100644
--- a/src/main.c
+++ b/src/main.c
@@ -508,6 +508,7 @@
 	guint signal, watchdog;
 	const char *watchdog_usec;
 
+	setvbuf(stdout, NULL, _IOLBF, 0);
 	init_defaults();
 
 	context = g_option_context_new(NULL);