1SD_EVENT_SOURCE_UNREF(3)     sd_event_source_unref    SD_EVENT_SOURCE_UNREF(3)
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NAME

6       sd_event_source_unref, sd_event_source_unrefp, sd_event_source_ref -
7       Increase or decrease event source reference counters
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SYNOPSIS

10       #include <systemd/sd-event.h>
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12       sd_event_source* sd_event_source_unref(sd_event_source *source);
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14       void sd_event_source_unrefp(sd_event_source **source);
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16       sd_event_source* sd_event_source_ref(sd_event_source *source);
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DESCRIPTION

19       sd_event_source_unref() may be used to decrement by one the reference
20       counter of the event source object specified as source. The reference
21       counter is initially set to one, when the event source is created with
22       calls such as sd_event_add_io(3) or sd_event_add_time(3). When the
23       reference counter reaches zero it is removed from its event loop object
24       and destroyed.
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26       sd_event_source_unrefp() is similar to sd_event_source_unref() but
27       takes a pointer to a pointer to an sd_event_source object. This call is
28       useful in conjunction with GCC's and LLVM's Clean-up Variable
29       Attribute[1]. Note that this function is defined as inline function.
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31       sd_event_source_ref() may be used to increase by one the reference
32       counter of the event source object specified as source.
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34       sd_event_source_unref(), sd_bus_creds_unrefp() and sd_bus_creds_ref()
35       execute no operation if the passed event source object is NULL.
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37       Note that event source objects stay alive and may be dispatched as long
38       as they have a reference counter greater than zero. In order to drop a
39       reference of an event source and make sure the associated event source
40       handler function is not called anymore it is recommended to combine a
41       call of sd_event_source_unref() with a prior call to
42       sd_event_source_set_enabled() with SD_EVENT_OFF.
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RETURN VALUE

45       sd_event_source_unref() always returns NULL.  sd_event_source_ref()
46       always returns the event source object passed in.
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NOTES

49       These APIs are implemented as a shared library, which can be compiled
50       and linked to with the libsystemd pkg-config(1) file.
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SEE ALSO

53       sd-event(3), sd_event_add_io(3), sd_event_add_time(3),
54       sd_event_add_child(3), sd_event_add_signal(3), sd_event_add_defer(3),
55       sd_event_source_set_enabled(3)
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NOTES

58        1. Clean-up Variable Attribute
59           https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html
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63systemd 239                                           SD_EVENT_SOURCE_UNREF(3)
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