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- jessie-backports 230-7~bpo8+2
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- unstable 240-1
SD_BUS_REQUEST_NAME(3) | sd_bus_request_name | SD_BUS_REQUEST_NAME(3) |
NAME¶
sd_bus_request_name, sd_bus_release_name - Request or release a well-known service name on a busSYNOPSIS¶
#include <systemd/sd-bus.h>
int sd_bus_request_name(sd_bus *bus,
const char *name,
uint64_t flags);
int sd_bus_release_name(sd_bus *bus,
const char *name);
DESCRIPTION¶
sd_bus_request_name() requests a well-known service name on a bus. It takes a bus connection, a valid bus name and a flags parameter. The flags parameter is a combination of the following flags: SD_BUS_NAME_ALLOW_REPLACEMENTAfter acquiring the name successfully, permit other peers
to take over the name when they try to acquire it with the
SD_BUS_NAME_REPLACE_EXISTING flag set. If
SD_BUS_NAME_ALLOW_REPLACEMENT is not set on the original request, such
a request by other peers will be denied.
SD_BUS_NAME_REPLACE_EXISTING
Take over the name if it is already acquired by another
peer, and that other peer has permitted takeover by setting
SD_BUS_NAME_ALLOW_REPLACEMENT while acquiring it.
SD_BUS_NAME_QUEUE
Queue the acquisition of the name when the name is
already taken.
sd_bus_release_name() releases an acquired well-known name. It takes a
bus connection and a valid bus name as parameters.
RETURN VALUE¶
On success, these calls return 0 or a positive integer. On failure, these calls return a negative errno-style error code. If SD_BUS_NAME_QUEUE is specified, sd_bus_request_name() will return 0 when the name is already taken by another peer and the client has been added to the queue for the name. In that case, the caller can subscribe to "NameOwnerChanged" signals to be notified when the name is successfully acquired. sd_bus_request_name() returns > 0 when the name has immediately been acquired successfully.ERRORS¶
Returned errors may indicate the following problems: -EALREADYThe caller already is the owner of the specified
name.
-EEXIST
The name has already been acquired by a different peer,
and SD_BUS_NAME_REPLACE_EXISTING was not specified or the other peer did not
specify SD_BUS_NAME_ALLOW_REPLACEMENT while acquiring the name.
-ESRCH
It was attempted to release a name that is currently not
registered on the bus.
-EADDRINUSE
It was attempted to release a name that is owned by a
different peer on the bus.
-EINVAL
A specified parameter is invalid. This is also generated
when the requested name is a special service name reserved by the D-Bus
specification, or when the operation is requested on a connection that does
not refer to a bus.
-ENOTCONN
The bus connection has been disconnected.
-ECHILD
The bus connection has been created in a different
process than the current one.
NOTES¶
The sd_bus_acquire_name() and sd_bus_release_name() interfaces are available as a shared library, which can be compiled and linked to with the libsystemd pkg-config(1) file.SEE ALSO¶
systemd(1), sd-bus(3), sd_bus_new(3)systemd 230 |