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

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

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

13       systemd-notify may be called by daemon scripts to notify the init
14       system about status changes. It can be used to send arbitrary
15       information, encoded in an environment-block-like list of strings. Most
16       importantly, it can be used for start-up completion notification.
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18       This is mostly just a wrapper around sd_notify() and makes this
19       functionality available to shell scripts. For details see sd_notify(3).
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21       The command line may carry a list of environment variables to send as
22       part of the status update.
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24       Note that systemd will refuse reception of status updates from this
25       command unless NotifyAccess= is set for the service unit this command
26       is called from.
27
28       Note that sd_notify() notifications may be attributed to units
29       correctly only if either the sending process is still around at the
30       time PID 1 processes the message, or if the sending process is
31       explicitly runtime-tracked by the service manager. The latter is the
32       case if the service manager originally forked off the process, i.e. on
33       all processes that match NotifyAccess=main or NotifyAccess=exec.
34       Conversely, if an auxiliary process of the unit sends an sd_notify()
35       message and immediately exits, the service manager might not be able to
36       properly attribute the message to the unit, and thus will ignore it,
37       even if NotifyAccess=all is set for it.
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39       systemd-notify will first attempt to invoke sd_notify() pretending to
40       have the PID of the invoking process. This will only succeed when
41       invoked with sufficient privileges. On failure, it will then fall back
42       to invoking it under its own PID. This behaviour is useful in order
43       that when the tool is invoked from a shell script the shell process —
44       and not the systemd-notify process — appears as sender of the message,
45       which in turn is helpful if the shell process is the main process of a
46       service, due to the limitations of NotifyAccess=all described above.
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OPTIONS

49       The following options are understood:
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51       --ready
52           Inform the init system about service start-up completion. This is
53           equivalent to systemd-notify READY=1. For details about the
54           semantics of this option see sd_notify(3).
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56       --pid=
57           Inform the init system about the main PID of the daemon. Takes a
58           PID as argument. If the argument is omitted, the PID of the process
59           that invoked systemd-notify is used. This is equivalent to
60           systemd-notify MAINPID=$PID. For details about the semantics of
61           this option see sd_notify(3).
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63       --uid=USER
64           Set the user ID to send the notification from. Takes a UNIX user
65           name or numeric UID. When specified the notification message will
66           be sent with the specified UID as sender, in place of the user the
67           command was invoked as. This option requires sufficient privileges
68           in order to be able manipulate the user identity of the process.
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70       --status=
71           Send a free-form status string for the daemon to the init systemd.
72           This option takes the status string as argument. This is equivalent
73           to systemd-notify STATUS=.... For details about the semantics of
74           this option see sd_notify(3).
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76       --booted
77           Returns 0 if the system was booted up with systemd, non-zero
78           otherwise. If this option is passed, no message is sent. This
79           option is hence unrelated to the other options. For details about
80           the semantics of this option, see sd_booted(3). An alternate way to
81           check for this state is to call systemctl(1) with the
82           is-system-running command. It will return "offline" if the system
83           was not booted with systemd.
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85       -h, --help
86           Print a short help text and exit.
87
88       --version
89           Print a short version string and exit.
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EXIT STATUS

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

95       Example 1. Start-up Notification and Status Updates
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97       A simple shell daemon that sends start-up notifications after having
98       set up its communication channel. During runtime it sends further
99       status updates to the init system:
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101           #!/bin/bash
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103           mkfifo /tmp/waldo
104           systemd-notify --ready --status="Waiting for data..."
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106           while : ; do
107                   read a < /tmp/waldo
108                   systemd-notify --status="Processing $a"
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110                   # Do something with $a ...
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112                   systemd-notify --status="Waiting for data..."
113           done
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SEE ALSO

116       systemd(1), systemctl(1), systemd.unit(5), sd_notify(3), sd_booted(3)
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120systemd 241                                                  SYSTEMD-NOTIFY(1)
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