sd_bus_get_n_queued_read(3) — Linux manual page

SD_BUS_GET_N_QUEUED_READ(3)   sd_bus_get_fd  SD_BUS_GET_N_QUEUED_READ(3)

NAME

       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

       #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

       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

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

   Errors
       Returned errors may indicate the following problems:

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

HISTORY

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

SEE ALSO

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

COLOPHON

       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 2024-06-14.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2024-06-13.)  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 257~devel                            SD_BUS_GET_N_QUEUED_READ(3)

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

---