sd_bus_attach_event(3) — Linux manual page


SD_BUS_ATTACH_EVENT(3)       sd_bus_attach_event      SD_BUS_ATTACH_EVENT(3)

NAME         top

       sd_bus_attach_event, sd_bus_detach_event, sd_bus_get_event - Attach a
       bus connection object to an event loop

SYNOPSIS         top

       #include <systemd/sd-bus.h>

       int sd_bus_attach_event(sd_bus *bus, sd_event *e, int priority);

       int sd_bus_detach_event(sd_bus *bus);

       sd_event *sd_bus_get_event(sd_bus *bus);

DESCRIPTION         top

       sd_bus_attach_event() attaches the specified bus connection object to
       an sd-event(3) event loop object at the specified priority (see
       sd_event_source_set_priority(3) for details on event loop
       priorities). When a bus connection object is attached to an event
       loop incoming messages will be automatically read and processed, and
       outgoing messages written, whenever the event loop is run. When the
       event loop is about to terminate, the bus connection is automatically
       flushed and closed (see sd_bus_set_close_on_exit(3) for details on
       this). By default bus connection objects are not attached to any
       event loop. When a bus connection object is attached to one it is not
       necessary to invoke sd_bus_wait(3) or sd_bus_process(3) as this
       functionality is handled automatically by the event loop.

       sd_bus_detach_event() detaches a bus object from its event loop.

       The sd_bus_get_event() returns the event loop object the specified
       bus object is currently attached to, or NULL if it is currently not
       attached to any.

       Note that sd_bus_attach_event() is only one of three supported ways
       to implement I/O event handling for bus connections. Alternatively
       use sd_bus_get_fd(3) for hooking up a bus connection object with
       external or manual event loops. Or use sd_bus_wait(3) as a simple
       synchronous, blocking I/O waiting call.

RETURN VALUE         top

       On success, sd_bus_attach_event() and sd_bus_detach_event() return 0
       or a positive integer. On failure, they return a negative errno-style
       error code.

       sd_bus_get_event() returns an event loop object or NULL.

       Returned errors may indicate the following problems:

           The bus connection has been created in a different process.

NOTES         top

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

SEE ALSO         top

       systemd(1), sd-bus(3), sd-event(3), sd_event_source_set_priority(3),
       sd_bus_set_close_on_exit(3), sd_bus_wait(3), sd_bus_get_fd(3)

COLOPHON         top

       This page is part of the systemd (systemd system and service manager)
       project.  Information about the project can be found at 
       ⟨⟩.  If you have a bug
       report for this manual page, see
       ⟨⟩.  This
       page was obtained from the project's upstream Git repository
       ⟨⟩ on 2020-09-18.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2020-09-18.)  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

systemd 246                                           SD_BUS_ATTACH_EVENT(3)

Pages that refer to this page: sd-bus(3)sd_bus_get_close_on_exit(3)sd_bus_get_events(3)sd_bus_get_exit_on_disconnect(3)sd_bus_get_fd(3)sd_bus_get_timeout(3)sd_bus_process(3)sd_bus_set_close_on_exit(3)sd_bus_set_exit_on_disconnect(3)sd_bus_set_fd(3)sd_bus_wait(3)30-systemd-environment-d-generator(7)systemd.directives(7)systemd.index(7)