sd_bus_message_set_destination, sd_bus_message_get_destination, sd_bus_message_get_path, sd_bus_message_get_interface, sd_bus_message_get_member, sd_bus_message_set_sender, sd_bus_message_get_sender — Set and query bus message addressing information
#include <systemd/sd-bus.h>
int sd_bus_message_set_destination( | sd_bus_message *message, |
const char *destination) ; |
const char* sd_bus_message_get_destination( | sd_bus_message *message) ; |
const char* sd_bus_message_get_path( | sd_bus_message *message) ; |
const char* sd_bus_message_get_interface( | sd_bus_message *message) ; |
const char* sd_bus_message_get_member( | sd_bus_message *message) ; |
int sd_bus_message_set_sender( | sd_bus_message *message, |
const char *sender) ; |
const char* sd_bus_message_get_sender( | sd_bus_message *message) ; |
sd_bus_message_set_destination()
sets the destination service name
for the specified bus message object. The specified name must be a valid unique or well-known
service name.
sd_bus_message_get_destination()
,
sd_bus_message_get_path()
,
sd_bus_message_get_interface()
, and
sd_bus_message_get_member()
return the destination, path, interface, and
member fields from message
header. The return value will be
NULL
is message
is NULL
or the
message is of a type that doesn't use those fields or the message doesn't have them set. See
sd_bus_message_new_method_call(3) and
sd_bus_message_set_destination(3)
for more discussion of those values.
sd_bus_message_set_sender()
sets the sender service name for the specified bus message
object. The specified name must be a valid unique or well-known service name. This function is useful only for
messages to send on direct connections as for connections to bus brokers the broker will fill in the destination
field anyway, and the sender field set by original sender is ignored.
sd_bus_message_get_sender()
returns the sender field from
message
.
When a string is returned, it is a pointer to internal storage, and may not be modified or
freed. It is only valid as long as the message
remains referenced and
this field hasn't been changed by a different call.
On success, these calls return 0 or a positive integer. On failure, these calls return a negative errno-style error code.
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_message_set_destination()
and
sd_bus_message_set_sender()
were added in version 237.
sd_bus_message_get_destination()
,
sd_bus_message_get_path()
,
sd_bus_message_get_interface()
,
sd_bus_message_get_member()
, and
sd_bus_message_get_sender()
were added in version 240.