diff --git a/src/libcharon/plugins/lookip/lookip.c b/src/libcharon/plugins/lookip/lookip.c
index d473c7022..6d82e1a17 100644
--- a/src/libcharon/plugins/lookip/lookip.c
+++ b/src/libcharon/plugins/lookip/lookip.c
@@ -203,7 +203,6 @@ static int interactive(int fd)
 		int res;
 
 		printf("> ");
-		fflush(stdout);
 
 		if (fgets(line, sizeof(line), stdin))
 		{
@@ -266,6 +265,8 @@ int main(int argc, char *argv[])
 		return 1;
 	}
 
+	setvbuf(stdout, NULL, _IOLBF, 0);
+
 	if (argc == 1)
 	{
 		res = interactive(fd);