sd_bus_slot_ref, sd_bus_slot_unref, sd_bus_slot_unrefp — Create and destroy references to a bus slot object
#include <systemd/sd-bus.h>
sd_bus_slot *sd_bus_slot_ref( | sd_bus_slot *slot) ; |
sd_bus_slot *sd_bus_slot_unref( | sd_bus_slot *slot) ; |
void sd_bus_slot_unrefp( | sd_bus_slot **slotp) ; |
sd_bus_slot_ref()
increases the reference counter of
slot
by one.
sd_bus_slot_unref()
decreases the reference counter of
slot
by one. Once the reference count has dropped to zero, slot object is
destroyed and cannot be used anymore, so further calls to sd_bus_slot_ref()
or sd_bus_slot_unref()
are illegal.
sd_bus_slot_unrefp()
is similar to
sd_bus_slot_unref()
but takes a pointer to a pointer to an
sd_bus_slot object. This call is useful in conjunction with GCC's and LLVM's Clean-up Variable
Attribute. See
sd_bus_new(3)
for an example how to use the cleanup attribute.
sd_bus_slot_ref()
and sd_bus_slot_unref()
execute no operation if the passed in bus object address is
NULL
. sd_bus_slot_unrefp()
will first dereference
its argument, which must not be NULL
, and will execute no operation if
that is NULL
.
These APIs are implemented as a shared
library, which can be compiled and linked to with the
libsystemd
pkg-config(1)
file.