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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | SEE ALSO | COLOPHON |
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SD_BUS_IS_OPEN(3) sd_bus_is_open SD_BUS_IS_OPEN(3)
sd_bus_is_open, sd_bus_is_ready - Check whether the bus connection is
open or ready
#include <systemd/sd-bus.h>
int sd_bus_is_open(sd_bus *bus);
int sd_bus_is_ready(sd_bus *bus);
sd_bus_is_open() checks whether the specified bus connection is open,
i.e. in the process of being established, already established or in
the process of being torn down. It returns zero when the connection
has not been started yet (i.e. sd_bus_start(3) or some equivalent
call has not been invoked yet), or is fully terminated again (for
example after sd_bus_close(3)), it returns positive otherwise.
sd_bus_is_ready() checks whether the specified connection is fully
established, i.e. completed the connection and authentication phases
of the protocol and received the Hello() method call response, and is
not in the process of being torn down again. It returns zero outside
of this state, and positive otherwise. Effectively, this function
returns positive while regular messages can be sent or received on
the connection.
To be notified when the connection is fully established, use
sd_bus_set_connected_signal(3) and install a match for the
Connected() signal on the "org.freedesktop.DBus.Local" interface. To
be notified when the connection is torn down again, install a match
for the Disconnected() signal on the "org.freedesktop.DBus.Local"
interface.
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.
These APIs are implemented as a shared library, which can be compiled
and linked to with the libsystemd pkg-config(1) file.
systemd(1), sd-bus(3), sd_bus_start(3), sd_bus_close(3),
sd_bus_set_connected_signal(3)
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 2020-11-01. (At that
time, the date of the most recent commit that was found in the repos‐
itory was 2020-11-01.) 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 im‐
provements to the information in this COLOPHON (which is not part of
the original manual page), send a mail to man-pages@man7.org
systemd 247 SD_BUS_IS_OPEN(3)
Pages that refer to this page: 30-systemd-environment-d-generator(7), systemd.directives(7), systemd.index(7)
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