|
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | SEE ALSO | NOTES | COLOPHON |
SD_EVENT_SOURCE_UNREF(3) sd_event_source_unref SD_EVENT_SOURCE_UNREF(3)
sd_event_source_unref, sd_event_source_unrefp, sd_event_source_ref,
sd_event_source_disable_unref, sd_event_source_disable_unrefp -
Increase or decrease event source reference counters
#include <systemd/sd-event.h>
sd_event_source* sd_event_source_unref(sd_event_source *source);
void sd_event_source_unrefp(sd_event_source **source);
sd_event_source* sd_event_source_ref(sd_event_source *source);
sd_event_source*
sd_event_source_disable_unref(sd_event_source *source);
void sd_event_source_disable_unrefp(sd_event_source **source);
sd_event_source_unref() may be used to decrement by one the reference
counter of the event source object specified as source. The reference
counter is initially set to one, when the event source is created
with calls such as sd_event_add_io(3) or sd_event_add_time(3). When
the reference counter reaches zero it is removed from its event loop
object and destroyed.
sd_event_source_unrefp() is similar to sd_event_source_unref() but
takes a pointer to a pointer to an sd_event_source object. This call
is useful in conjunction with GCC's and LLVM's Clean-up Variable
Attribute[1]. Note that this function is defined as inline function.
sd_event_source_ref() may be used to increase by one the reference
counter of the event source object specified as source.
sd_event_source_unref(), sd_bus_creds_unrefp() and sd_bus_creds_ref()
execute no operation if the passed event source object is NULL.
Note that event source objects stay alive and may be dispatched as
long as they have a reference counter greater than zero. In order to
drop a reference of an event source and make sure the associated
event source handler function is not called anymore it is recommended
to combine a call of sd_event_source_unref() with a prior call to
sd_event_source_set_enabled() with SD_EVENT_OFF or call
sd_event_source_disable_unref(), see below.
sd_event_source_disable_unref() combines a call to
sd_event_source_set_enabled() with SD_EVENT_OFF with
sd_event_source_unref(). This ensures that the source is disabled
before the local reference to it is lost. The source parameter is
allowed to be NULL.
sd_event_source_disable_unrefp() is similar to
sd_event_source_unrefp(), but in addition disables the source first.
This call is useful in conjunction with GCC's and LLVM's Clean-up
Variable Attribute[1]. Note that this function is defined as inline
function.
sd_event_source_unref() and sd_event_source_disable_unref() always
return NULL. sd_event_source_ref() always returns the event source
object passed in.
These APIs are implemented as a shared library, which can be compiled
and linked to with the libsystemd pkg-config(1) file.
sd-event(3), sd_event_add_io(3), sd_event_add_time(3),
sd_event_add_signal(3), sd_event_add_child(3),
sd_event_add_inotify(3), sd_event_add_defer(3),
sd_event_source_set_enabled(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_EVENT_SOURCE_UNREF(3)
Pages that refer to this page: 30-systemd-environment-d-generator(7) , systemd.index(7)