sd_bus_add_match
systemd
Julian
Orth
ju.orth@gmail.com
sd_bus_add_match
3
sd_bus_add_match
Add a match rule for message dispatching
#include <systemd/sd-bus.h>
int sd_bus_add_match
sd_bus *bus
sd_bus_slot **slot
const char *match
sd_bus_message_handler_t callback
void *userdata
typedef int (*sd_bus_message_handler_t)
sd_bus_message *m
void *userdata
sd_bus_error *ret_error
Description
sd_bus_add_match() adds a match rule used to dispatch
incoming messages. The syntax of the rule passed in
match is described in the
D-Bus Specification.
The message m passed to the callback is only
borrowed, that is, the callback should not call
sd_bus_message_unref3
on it. If the callback wants to hold on to the message beyond the lifetime
of the callback, it needs to call
sd_bus_message_ref3
to create a new reference.
If an error occurs during the callback invocation, the callback should
return a negative error number. If it wants other callbacks that match the
same rule to be called, it should return 0. Otherwise it should return a
positive integer.
Return Value
On success, sd_bus_add_match() returns 0 or a
positive integer. On failure, it returns a negative errno-style error
code.
See Also
systemd1,
sd-bus3,