|
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | SEE ALSO | NOTES | COLOPHON |
SD_BUS_SLOT_REF(3) sd_bus_slot_ref SD_BUS_SLOT_REF(3)
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[1]. 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.
sd_bus_slot_ref() always returns the argument.
sd_bus_slot_unref() always returns NULL.
These APIs are implemented as a shared library, which can be compiled
and linked to with the libsystemd pkg-config(1) file.
systemd(1), sd-bus(3), sd_bus_new(3), sd_bus_message_new(3),
sd_bus_call_method_async(3)
1. Clean-up Variable Attribute
https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html
This page is part of the systemd (systemd system and service manager)
project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have a bug
report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩. This
page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2020-08-13. (At that
time, the date of the most recent commit that was found in the repos‐
itory was 2020-08-11.) If you discover any rendering problems in
this HTML version of the page, or you believe there is a better or
more up-to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not part
of the original manual page), send a mail to man-pages@man7.org
systemd 246 SD_BUS_SLOT_REF(3)
Pages that refer to this page: sd_bus_slot_get_description(3) , sd_bus_slot_set_description(3) , 30-systemd-environment-d-generator(7) , systemd.directives(7) , systemd.index(7)