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sd_varlink_is_connected(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | HISTORY | SEE ALSO | COLOPHON 

SD_VARLI...CONNECTED(3)  sd_varlink_is_connected  SD_VARLI...CONNECTED(3)

NAME         top

       sd_varlink_is_connected, sd_varlink_is_idle - Query if a Varlink
       connection object is currently connected or idle

SYNOPSIS         top

       #include <systemd/sd-varlink.h>

       int sd_varlink_is_connected(sd_varlink *link);

       int sd_varlink_is_idle(sd_varlink *link);

DESCRIPTION         top

       sd_varlink_is_connected() checks whether the specified Varlink
       connection object is currently connected or whether it has been
       fully disconnected already.

       sd_varlink_is_idle() checks whether the specified Varlink
       connection object is currently connected but idle, i.e. may accept
       a method call for enqueuing (if client side of a Varlink
       connection) or is waiting for more incoming method calls to arrive
       (if server side of a Varlink connection).

RETURN VALUE         top

       If the connection is currently connected sd_varlink_is_connected()
       returns a positive non-zero value. If disconnected it returns 0.
       If the connection currently is idle sd_varlink_is_idle() returns a
       positive non-zero integer. If not, returns 0. On failure, both
       functions return a negative errno error code.

   Errors
       Returned errors may indicate the following problems:

       -EINVAL
           The specified Varlink connection is invalid.

NOTES         top

       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         top

       sd_varlink_is_connected() was added in version 259.

       sd_varlink_is_idle() was added in version 257.

SEE ALSO         top

       systemd(1), sd-varlink(3)

COLOPHON         top

       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 2026-01-16.  (At that
       time, the date of the most recent commit that was found in the
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       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 260~devel                                 SD_VARLI...CONNECTED(3)

Pages that refer to this page: systemd.directives(7),  systemd.index(7)

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