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  4. systemd-notify(1)

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

NAME

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

SYNOPSIS

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

DESCRIPTION

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.

OPTIONS

The following options are understood:

--ready

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).

--pid=

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).

--uid=USER

Set the user ID to send the notification from. Takes a UNIX user name or numeric UID. When specified the notification message will be sent with the specified UID as sender, in place of the user the command was invoked as. This option requires sufficient privileges in order to be able manipulate the user identity of the process.

--status=

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).

--booted

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).

--readahead=

Controls disk read-ahead operations. The argument must be a string, and either "cancel", "done" or "noreplay". For details about the semantics of this option see sd_readahead(3).

-h, --help

Print a short help text and exit.

--version

Print a short version string and exit.

EXIT STATUS

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

EXAMPLE

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:

#!/bin/bash
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..."
done

SEE ALSO

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

systemd 219