SYSTEMD-NOTIFY(1)              systemd-notify              SYSTEMD-NOTIFY(1)

NAME         top

       systemd-notify - Notify service manager about start-up completion and
       other daemon status changes

SYNOPSIS         top

       systemd-notify [OPTIONS...] [VARIABLE=VALUE...]

DESCRIPTION         top

       systemd-notify may be called by daemon scripts to notify the init
       system about status changes. It can be used to send arbitrary
       information, encoded in an environment-block-like list of strings.
       Most importantly, it can be used for start-up completion

       This is mostly just a wrapper around sd_notify() and makes this
       functionality available to shell scripts. For details see

       The command line may carry a list of environment variables to send as
       part of the status update.

       Note that systemd will refuse reception of status updates from this
       command unless NotifyAccess= is set for the service unit this command
       is called from.

       Note that sd_notify() notifications may be attributed to units
       correctly only if either the sending process is still around at the
       time PID 1 processes the message, or if the sending process is
       explicitly runtime-tracked by the service manager. The latter is the
       case if the service manager originally forked off the process, i.e.
       on all processes that match NotifyAccess=main or NotifyAccess=exec.
       Conversely, if an auxiliary process of the unit sends an sd_notify()
       message and immediately exits, the service manager might not be able
       to properly attribute the message to the unit, and thus will ignore
       it, even if NotifyAccess=all is set for it.

       systemd-notify will first attempt to invoke sd_notify() pretending to
       have the PID of the invoking process. This will only succeed when
       invoked with sufficient privileges. On failure, it will then fall
       back to invoking it under its own PID. This behaviour is useful in
       order that when the tool is invoked from a shell script the shell
       process — and not the systemd-notify process — appears as sender of
       the message, which in turn is helpful if the shell process is the
       main process of a service, due to the limitations of NotifyAccess=all
       described above.

OPTIONS         top

       The following options are understood:

           Inform the init system about service start-up completion. This is
           equivalent to systemd-notify READY=1. For details about the
           semantics of this option see sd_notify(3).

           Inform the init system about the main PID of the daemon. Takes a
           PID as argument. If the argument is omitted, the PID of the
           process that invoked systemd-notify is used. This is equivalent
           to systemd-notify MAINPID=$PID. For details about the semantics
           of this option see sd_notify(3).

           Send a free-form status string for the daemon to the init
           systemd. This option takes the status string as argument. This is
           equivalent to systemd-notify STATUS=.... For details about the
           semantics of this option see sd_notify(3).

           Returns 0 if the system was booted up with systemd, non-zero
           otherwise. If this option is passed, no message is sent. This
           option is hence unrelated to the other options. For details about
           the semantics of this option, see sd_booted(3). An alternate way
           to check for this state is to call systemctl(1) with the
           is-system-running command. It will return "offline" if the system
           was not booted with systemd.

       -h, --help
           Print a short help text and exit.

           Print a short version string and exit.

EXIT STATUS         top

       On success, 0 is returned, a non-zero failure code otherwise.

EXAMPLE         top

       Example 1. Start-up Notification and Status Updates

       A simple shell daemon that sends start-up notifications after having
       set up its communication channel. During runtime it sends further
       status updates to the init system:


           mkfifo /tmp/waldo
           systemd-notify --ready --status="Waiting for data..."

           while : ; do
                   read a < /tmp/waldo
                   systemd-notify --status="Processing $a"

                   # Do something with $a ...

                   systemd-notify --status="Waiting for data..."

SEE ALSO         top

       systemd(1), systemctl(1), systemd.unit(5), sd_notify(3), sd_booted(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 2019-07-28.  (At that
       time, the date of the most recent commit that was found in the repos‐
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       of the original manual page), send a mail to

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