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


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


   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 notification.

   This is mostly just a wrapper around sd_notify() and makes this
   functionality available to shell scripts. For details see sd_notify(3).

   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=all is set for the service unit this
   command is called from.


   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.


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


   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..."


   systemd(1), systemctl(1), systemd.unit(5), sd_notify(3), sd_booted(3)


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