int bus_message_new_synthetic_error(sd_bus *bus, uint64_t serial, const sd_bus_error *e, sd_bus_message **m);
int bus_message_remarshal(sd_bus *bus, sd_bus_message **m);
int bus_message_new_synthetic_error(sd_bus *bus, uint64_t serial, const sd_bus_error *e, sd_bus_message **m);
int bus_message_remarshal(sd_bus *bus, sd_bus_message **m);