diff --git a/term/error.c b/term/error.c
index 2b0bc49..96f9633 100644
--- a/term/error.c
+++ b/term/error.c
@@ -19,18 +19,18 @@ static void get_error_id(
 	fx_stringstream *id = fx_stringstream_create_with_buffer(out, max);
 
 	if (vendor_name) {
-		fx_stream_write_string(id, vendor_name, NULL);
+		fx_stream_write_cstr(id, vendor_name, NULL);
 	}
 
 	if (error_name) {
 		if (vendor_name) {
-			fx_stream_write_string(id, ".", NULL);
+			fx_stream_write_cstr(id, ".", NULL);
 		}
 
-		fx_stream_write_string(id, error_name, NULL);
+		fx_stream_write_cstr(id, error_name, NULL);
 	} else {
 		if (vendor_name) {
-			fx_stream_write_string(id, "#", NULL);
+			fx_stream_write_cstr(id, "#", NULL);
 		}
 
 		fx_stream_write_fmt(id, NULL, "%ld", code);
@@ -125,6 +125,10 @@ static void print_content(
 	const struct fx_error_template_parameter *params, size_t nr_params,
 	const char *s)
 {
+	if (!s) {
+		return;
+	}
+
 	char modifier = 0;
 	char buf[128];
 	size_t buf_len = 0;