sd_bus_get_n_queued_read(3) — Linux manual page



NAME         top

       sd_bus_get_n_queued_read, sd_bus_get_n_queued_write - Get the
       number of pending bus messages in the read and write queues of a
       bus connection object

SYNOPSIS         top

       #include <systemd/sd-bus.h>

       int sd_bus_get_n_queued_read(sd_bus *bus, uint64_t *ret);

       int sd_bus_get_n_queued_write(sd_bus *bus, uint64_t *ret);

DESCRIPTION         top

       sd_bus_get_n_queued_read() may be used to query the number of bus
       messages in the read queue of a bus connection object. The read
       queue contains all messages read from the transport medium (e.g.
       network socket) but not yet processed locally. The function
       expects two arguments: the bus object to query, and a pointer to
       a 64-bit counter variable to write the current queue size to. Use
       sd_bus_process() in order to process queued messages, i.e. to
       reduce the size of the read queue (as well as, in fact, the write
       queue, see below).

       Similarly, sd_bus_get_n_queued_write() may be used to query the
       number of currently pending bus messages in the write queue of a
       bus connection object. The write queue contains all messages
       enqueued into the connection with a call such as sd_bus_send()
       but not yet written to the transport medium. The expected
       arguments are similar to sd_bus_get_n_queued_read(). Here too,
       use sd_bus_process() to reduce the size of the write queue.
       Alternatively, use sd_bus_flush() to synchronously write out any
       pending bus messages until the write queue is empty.

RETURN VALUE         top

       On success, these functions return 0 or a positive integer. On
       failure, they return a negative errno-style error code.

       Returned errors may indicate the following problems:

           The bus connection was created in a different process,
           library or module instance.

HISTORY         top

       sd_bus_get_n_queued_read() and sd_bus_get_n_queued_write() were
       added in version 238.

SEE ALSO         top

       systemd(1), sd-bus(3), sd_bus_process(3), sd_bus_send(3),

COLOPHON         top

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systemd 255                                  SD_BUS_GET_N_QUEUED_READ(3)

Pages that refer to this page: sd-bus(3)systemd.directives(7)systemd.index(7)