1SD_BUS_SLOT_REF(3)              sd_bus_slot_ref             SD_BUS_SLOT_REF(3)
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NAME

6       sd_bus_slot_ref, sd_bus_slot_unref, sd_bus_slot_unrefp - Create and
7       destroy references to a bus slot object
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SYNOPSIS

10       #include <systemd/sd-bus.h>
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12       sd_bus_slot *sd_bus_slot_ref(sd_bus_slot *slot);
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14       sd_bus_slot *sd_bus_slot_unref(sd_bus_slot *slot);
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16       void sd_bus_slot_unrefp(sd_bus_slot **slotp);
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DESCRIPTION

19       sd_bus_slot_ref() increases the internal reference counter of slot by
20       one.
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22       sd_bus_slot_unref() decreases the internal reference counter of slot by
23       one. Once the reference count has dropped to zero, slot object is
24       destroyed and cannot be used anymore, so further calls to
25       sd_bus_slot_ref() or sd_bus_slot_unref() are illegal.
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27       sd_bus_slot_unrefp() is similar to sd_bus_slot_unref() but takes a
28       pointer to a pointer to an sd_bus_slot object. This call is useful in
29       conjunction with GCC's and LLVM's Clean-up Variable Attribute[1]. See
30       sd_bus_new(3) for an example how to use the cleanup attribute.
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32       sd_bus_slot_ref() and sd_bus_slot_unref() execute no operation if the
33       passed in bus object address is NULL.  sd_bus_slot_unrefp() will first
34       dereference its argument, which must not be NULL, and will execute no
35       operation if that is NULL.
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RETURN VALUE

38       sd_bus_slot_ref() always returns the argument.
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40       sd_bus_slot_unref() always returns NULL.
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NOTES

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

47       systemd(1), sd-bus(3), sd_bus_new(3), sd_bus_message_new(3),
48       sd_bus_call_method_async(3)
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NOTES

51        1. Clean-up Variable Attribute
52           https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html
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56systemd 251                                                 SD_BUS_SLOT_REF(3)
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