systemd sd_bus_set_server 3 sd_bus_set_server sd_bus_get_bus_id Configure server mode for a bus object #include <systemd/sd-bus.h> int sd_bus_set_server sd_bus *bus int b sd_id128_t id int sd_bus_get_bus_id sd_bus *bus sd_id128_t *id sd_bus_set_server() configures the bus object as a server for direct D-Bus connections. b enables/disables the server mode. If zero, the server mode is disabled. Otherwise, the server mode is enabled. Configuring a bus object as a server is required to allow establishing direct connections between two peers without going via the D-Bus daemon. id must contain a 128-bit integer id for the server. If clients add a guid field to their D-Bus address string, the server id must match this guid or the D-Bus authentication handshake will fail. If no specific id is defined for the server, sd_id128_randomize3 can be used to generate a random id instead. sd_bus_get_bus_id() stores the D-Bus server id configured using sd_bus_set_server() (for server bus objects) or received during D-Bus authentication (for client bus objects) in id. On success, these functions return a non-negative integer. On failure, they return a negative errno-style error code. Returned errors may indicate the following problems: -ECHILD The bus connection has been created in a different process. -EPERM The bus connection has already been started. -ENOPKG The bus cannot be resolved. -EINVAL A required parameter was NULL or b was zero and id did not equal SD_ID128_NULL. -ENOTCONN The bus is not connected. systemd1, sd-bus3