+int varlink_observe(Varlink *v, const char *method, JsonVariant *parameters) {
+ _cleanup_(json_variant_unrefp) JsonVariant *m = NULL;
+ int r;
+
+ assert_return(v, -EINVAL);
+ assert_return(method, -EINVAL);
+
+ if (v->state == VARLINK_DISCONNECTED)
+ return -ENOTCONN;
+ /* Note that we don't allow enqueuing multiple method calls when we are in more/continues mode! We
+ * thus insist on an idle client here. */
+ if (v->state != VARLINK_IDLE_CLIENT)
+ return -EBUSY;
+
+ r = varlink_sanitize_parameters(¶meters);
+ if (r < 0)
+ return r;
+
+ r = json_build(&m, JSON_BUILD_OBJECT(
+ JSON_BUILD_PAIR("method", JSON_BUILD_STRING(method)),
+ JSON_BUILD_PAIR("parameters", JSON_BUILD_VARIANT(parameters)),
+ JSON_BUILD_PAIR("more", JSON_BUILD_BOOLEAN(true))));
+ if (r < 0)
+ return r;
+
+ r = varlink_enqueue_json(v, m);
+ if (r < 0)
+ return r;
+
+
+ varlink_set_state(v, VARLINK_AWAITING_REPLY_MORE);
+ v->n_pending++;
+ v->timestamp = now(CLOCK_MONOTONIC);
+
+ return 0;
+}
+
+int varlink_observeb(Varlink *v, const char *method, ...) {
+ _cleanup_(json_variant_unrefp) JsonVariant *parameters = NULL;
+ va_list ap;
+ int r;
+
+ assert_return(v, -EINVAL);
+
+ va_start(ap, method);
+ r = json_buildv(¶meters, ap);
+ va_end(ap);
+
+ if (r < 0)
+ return r;
+
+ return varlink_observe(v, method, parameters);
+}
+