Index · Directives systemd 257~rc3

Name

sd_bus_slot_get_bus, sd_bus_slot_get_current_handler, sd_bus_slot_get_current_message, sd_bus_slot_get_current_userdata — Query information attached to a bus slot object

Synopsis

#include <systemd/sd-bus.h>
typedef int (*sd_bus_message_handler_t)(sd_bus_message *m,
 void *userdata,
 sd_bus_error *ret_error);
 
sd_bus *sd_bus_slot_get_bus(sd_bus_slot *slot);
 
sd_bus_message_handler_t sd_bus_slot_get_current_handler (sd_bus_slot *slot);
 
sd_bus_message *sd_bus_slot_get_current_message(sd_bus_slot *slot);
 
void *sd_bus_slot_get_current_userdata(sd_bus_slot *slot);
 

Description

sd_bus_slot_get_bus() returns the bus object that message slot is attached to.

sd_bus_slot_get_current_handler(), sd_bus_slot_get_current_message() and sd_bus_slot_get_current_userdata() return the current handler, message and userdata respectively of the bus slot is attached to if we're currently executing the callback associated with slot.

Return Value

sd_bus_slot_get_bus() always returns the bus object.

On success, sd_bus_slot_get_current_handler(), sd_bus_slot_get_current_message() and sd_bus_slot_get_current_userdata() return the requested object. On failure, they return NULL.

Notes

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.

History

sd_bus_slot_get_bus(), sd_bus_slot_get_current_handler(), sd_bus_slot_get_current_message(), and sd_bus_slot_get_current_userdata() were added in version 246.

See Also

systemd(1), sd-bus(3)