diff --git a/test/fpurge.c b/test/fpurge.c
index 8f2e996..03f107f 100644
--- a/test/fpurge.c
+++ b/test/fpurge.c
@@ -32,6 +32,9 @@ main()
 	static FILE fp_bad;
 	FILE *fp;
 
+	if (fpurge(NULL) == 0)
+		return 1;
+
 	if (fpurge(&fp_bad) == 0)
 		return 1;