Index · Directives systemd 255


sd_bus_add_object_manager — Add a D-Bus object manager for a D-Bus object sub-tree


#include <systemd/sd-bus.h>
int sd_bus_add_object_manager(sd_bus *bus,
 sd_bus_slot **slot,
 const char *path);


sd_bus_add_object_manager() installs a handler for the given path that implements the GetManagedObjects() method of the org.freedesktop.DBus.ObjectManager interface. See org.freedesktop.DBus.ObjectManager for more information.

To implement the InterfacesAdded and InterfacesRemoved signals of the org.freedesktop.DBus.ObjectManager interface, call sd_bus_emit_interfaces_added(3) and sd_bus_emit_interfaces_removed(3) whenever interfaces are added or removed from the sub-tree, respectively.

When sd_bus_add_object_manager() succeeds, a slot is created internally. If the output parameter slot is NULL, a "floating" slot object is created, see sd_bus_slot_set_floating(3). Otherwise, a pointer to the slot object is returned. In that case, the reference to the slot object should be dropped when the object manager is not needed anymore, see sd_bus_slot_unref(3).

Return Value

On success, sd_bus_add_object_manager() returns a non-negative integer. On failure, it returns a negative errno-style error code.


Returned errors may indicate the following problems:


One of the required parameters is NULL or path is not a valid object path.

Added in version 246.


The bus cannot be resolved.

Added in version 246.


The bus was created in a different process, library or module instance.

Added in version 246.


Memory allocation failed.

Added in version 246.


Functions described here are available as a shared library, which can be compiled against and linked to with the libsystemd pkg-config(1) file.

The code described here uses getenv(3), which is declared to be not multi-thread-safe. This means that the code calling the functions described here must not call setenv(3) from a parallel thread. It is recommended to only do calls to setenv() from an early phase of the program when no other threads have been started.


sd_bus_add_object_manager() was added in version 246.

See Also

sd-bus(3), busctl(1), sd_bus_add_object_vtable(3), sd_bus_emit_interfaces_added(3), sd_bus_slot_unref(3)