NAME

       sd_bus_set_connected_signal, sd_bus_get_connected_signal - Control emission of local connection
       establishment signal on bus connections

SYNOPSIS

       #include <systemd/sd-bus.h>

       int sd_bus_set_connected_signal(sd_bus *bus, int b);

       int sd_bus_get_connected_signal(sd_bus *bus);

DESCRIPTION

       sd_bus_set_connected_signal() may be used to control whether a local, synthetic Connected() signal
       message shall be generated and enqueued for dispatching when the connection is fully established. If the
       b parameter is zero the message is not generated (the default), otherwise it is generated.

       sd_bus_get_connected_signal() may be used to query whether this feature is enabled. It returns zero if
       not, positive otherwise.

       The Connected() signal message is generated from the "org.freedesktop.DBus.Local" service and interface,
       and "/org/freedesktop/DBus/Local" object path. Use sd_bus_match_signal_async(3) to match on this signal.

       This message is particularly useful on slow transports where connections take a long time to be
       established. This is especially the case when sd_bus_set_watch_bind(3) is used. The signal is generated
       when the sd_bus_is_ready(3) returns positive for the first time.

       The Connected() signal corresponds with the Disconnected() signal that is synthesized locally when the
       connection is terminated. The latter is generated unconditionally however, unlike the former which needs
       to be enabled explicitly before it is generated, with sd_bus_set_connected_signal().

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 has been created in a different process, library or module instance.

NOTES

       Functions described here are available as a shared library, which can be compiled against and linked to
       with the libsystemd pkg-config(1) file.

       The code described here uses getenv(3), which is declared to be not multi-thread-safe. This means that
       the code calling the functions described here must not call setenv(3) from a parallel thread. It is
       recommended to only do calls to setenv() from an early phase of the program when no other threads have
       been started.

HISTORY

       sd_bus_set_connected_signal() and sd_bus_get_connected_signal() were added in version 237.

SEE ALSO

       systemd(1), sd-bus(3), sd_bus_match_signal_async(3), sd_bus_set_watch_bind(3), sd_bus_is_ready(3)