diff --git a/tester/setup_tester.c b/tester/setup_tester.c
index 21fcfd091..63a8616d5 100644
--- a/tester/setup_tester.c
+++ b/tester/setup_tester.c
@@ -132,7 +132,9 @@ static void linphone_lpconfig_from_file_zerolen_value(){
 	char* rc_path = ms_strdup_printf("%s/rcfiles/%s", liblinphone_tester_file_prefix, zero_rc_file);
 	LpConfig* conf;
 
-	conf = lp_config_new(rc_path);
+	/* not using lp_config_new() because it expects a readable file, and iOS (for instance)
+	   stores the app bundle in read-only */
+	conf = lp_config_new_with_factory(NULL, rc_path);
 
 	CU_ASSERT_STRING_EQUAL(lp_config_get_string(conf,"test","zero_len","LOL"),"LOL");
 	CU_ASSERT_STRING_EQUAL(lp_config_get_string(conf,"test","non_zero_len",""),"test");