SYSTEMD-SOFT-REBOOT.SERVICE(8)                     systemd-soft-reboot.service

<?><?><?> (NAME)
       systemd-soft-reboot.service - <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?> <?><?><?><?>
       <?><?><?><?><?><?> <?><?> systemd

<?><?><?><?><?> <?><?><?><?><?> (SYNOPSIS)
       systemd-soft-reboot.service

<?><?><?><?><?><?><?> (DESCRIPTION)
       systemd-soft-reboot.service <?><?> <?><?><?><?><?> <?><?><?><?><?><?>
       <?><?><?> <?><?> <?><?><?><?> soft-reboot.target
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?> <?> <?><?><?><?><?>
       <?><?><?><?><?> <?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> <?><?>
       <?><?><?><?> <?><?><?><?><?><?> (userspace-only) <?><?><?>.
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?> SIGTERM <?><?> <?><?> <?><?> <?><?><?><?><?><?>
       <?><?> <?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?><?><?><?> (<?><?><?> <?><?><?><?><?>
       <?><?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>) <?>
       <?><?><?> <?><?> <?><?> <?><?> SIGKILL <?><?><?><?><?>
       <?><?><?><?><?><?>. <?><?><?> <?><?><?><?><?><?><?><?><?>
       /run/nextroot/ <?><?><?><?> <?><?><?><?><?> <?><?><?><?> (<?><?>
       <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?> <?><?><?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?> <?><?> <?><?><?><?><?>
       <?><?><?><?><?><?> <?><?> <?><?> <?><?> <?><?> <?><?><?><?><?>
       <?><?><?><?>)<?> <?><?><?><?> <?><?><?><?><?> <?><?><?><?> <?><?>
       <?><?> <?><?> <?><?><?><?><?> <?><?><?><?><?><?>. <?><?><?>
       <?><?><?><?> <?><?><?><?><?> <?><?> <?><?> <?><?><?> <?><?><?><?><?>
       <?><?><?><?> <?><?><?><?> (<?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?><?> <?><?><?>) <?><?><?><?><?><?> <?><?><?><?>
       <?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?> <?><?>
       <?><?><?><?><?><?> <?><?><?> <?><?><?><?> <?><?> <?><?> <?><?>
       <?><?><?><?> <?><?><?><?><?><?>.

       <?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?> <?><?><?><?><?><?> <?><?>
       <?><?> <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> (downtime)
       <?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?> <?><?><?><?><?>
       <?><?><?> <?><?><?> <?><?><?><?><?><?><?>:

       o   <?><?><?> <?><?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?> systemd-shutdown(8)
           <?><?><?><?><?><?><?><?><?><?> <?><?><?> <?><?><?>.

       o   <?><?><?> <?><?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?> <?><?><?><?><?><?> <?><?> <?><?><?><?><?><?> initrd.

       o   <?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?>.

       o   <?><?><?><?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?><?><?><?><?><?> (firmware).

       o   <?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?>
           <?><?><?> (boot loader).

       o   <?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?> (kernel).

       o   <?><?><?><?><?><?><?><?> <?><?><?><?><?> initrd.

       <?><?> <?><?><?> <?><?><?><?> <?><?><?> <?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?>
       <?><?><?> <?><?> <?><?><?><?><?> <?><?><?><?>:

       o   <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
           <?><?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?> <?><?>
           <?><?><?><?><?> <?><?><?> <?><?><?><?><?> <?><?><?><?><?><?>.

       o   <?><?><?><?><?><?><?> <?><?><?><?> (<?><?><?><?><?>
           <?><?><?><?><?><?><?> /proc/sys/<?> <?><?><?><?><?> <?><?>
           "sysctl"<?> <?><?> <?><?><?><?><?><?><?> /sys/)
           <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>.

       <?><?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?> <?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?> <?><?> <?><?><?><?> <?><?> <?><?><?><?><?><?> <?><?><?>
       <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> <?><?><?><?>
       <?><?><?> <?><?><?><?><?> <?><?><?><?> (kernel live-patching) <?>
       <?><?><?><?><?><?><?><?> /etc/sysctl.d/ <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?> <?><?><?><?>.

<?><?><?><?><?><?> <?><?><?><?><?> (RESOURCE PASS-THROUGH)
       <?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?>
       <?><?> <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?><?>
       <?><?><?><?><?> <?><?><?><?> <?><?> <?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?> <?><?><?><?>
       <?><?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?>.
       <?><?><?><?><?><?> <?><?><?><?>:

       o   <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?> <?><?> <?><?><?><?><?>
           <?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?> <?><?><?>
           <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?> <?> <?><?>
           <?><?><?><?> <?><?> <?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?>
           <?><?><?><?> <?><?><?><?> <?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?>. <?><?><?><?> <?><?><?> <?><?><?><?>
           <?><?><?><?><?><?> <?><?><?><?> DefaultDependencies=no <?><?>
           <?><?><?><?><?> <?><?><?><?> (<?> <?><?> <?><?><?><?><?>
           <?><?><?><?> Conflicts=shutdown.target <?><?> <?><?><?><?><?>
           <?><?> <?><?><?><?><?><?><?> <?><?><?><?>) <?><?>
           <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?> <?><?> <?><?><?>
           <?><?><?><?><?> <?><?> <?><?><?> <?><?><?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?><?><?><?><?><?>. <?><?> <?><?>
           FileDescriptorStorePreserve= <?><?><?><?><?><?><?> <?><?><?><?>
           <?><?> <?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?> <?><?> <?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?> <?><?><?><?><?> (pinned) <?><?><?><?>
           <?><?><?><?><?>. <?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?><?>
           <?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?>
           systemd.service(5) <?><?><?><?><?><?> <?><?><?><?>.

       o   <?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?> <?><?> <?><?><?><?><?><?><?> .socket <?><?>
           <?><?><?><?><?> <?><?> <?><?><?><?><?><?> <?><?> <?><?><?>
           <?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?> <?><?><?>
           (<?> <?><?><?><?> <?><?><?><?><?>) <?><?><?><?>
           <?><?><?><?><?><?><?><?>. (<?><?> <?><?><?><?><?>
           DefaultDependencies=no <?><?><?><?> <?><?><?><?><?><?>.)

       o   <?><?><?><?><?> <?><?><?><?> /run/ <?><?><?><?><?><?><?> (mounted)
           <?> <?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?> <?>
           <?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?>
           <?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?> <?><?><?>
           <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
           <?><?><?><?> <?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?><?><?>
           <?><?><?>.

       o   <?><?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?><?><?>
           <?><?> <?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?> <?><?> <?><?> <?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?> (<?><?> <?><?><?> <?><?><?> <?><?>
           <?><?><?><?> DefaultDependencies=no <?><?> <?><?><?>
           <?><?><?><?><?><?>)<?> <?><?><?><?> <?><?><?> <?><?> <?><?><?>
           <?><?><?><?><?><?><?> <?><?> <?><?> soft-reboot <?> <?><?><?><?>
           <?><?><?><?> <?><?><?><?> <?><?> <?><?><?><?><?> <?><?><?>
           <?><?><?><?><?> <?><?><?><?>. <?><?><?><?><?> <?><?><?><?><?><?>
           <?><?><?><?> <?><?> <?><?><?><?><?><?><?> <?><?>
           SurviveFinalKillSignal=yes <?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?> <?><?> <?><?><?><?><?> <?><?><?><?><?> <?><?><?><?> SIGTERM
           <?> SIGKILL <?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?> <?>
           <?><?><?><?><?><?> <?><?> <?><?><?><?> IgnoreOnIsolate=yes
           <?><?><?><?><?> <?><?><?><?> <?><?> <?><?> <?><?><?><?><?>
           <?><?><?> <?><?> <?><?><?><?><?> <?><?><?><?><?><?><?> (isolate)
           <?><?><?><?><?><?><?> <?><?><?>. <?><?><?><?><?> <?><?><?><?><?><?>
           <?><?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?> <?><?> <?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?> <?><?><?><?>
           <?><?><?><?><?> <?> <?><?><?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?>. <?><?> <?><?><?><?><?><?> <?><?><?><?><?>
           <?><?><?><?> <?><?> <?><?> basic.target <?><?><?><?> <?><?><?><?>
           <?><?> <?><?> <?><?><?><?><?> <?><?><?><?> <?><?> <?><?><?><?>
           <?><?><?> <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?>.
           <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?><?><?>
           <?><?> <?><?> <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?> <?><?>
           <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?>
           <?><?><?><?><?><?><?> <?><?><?><?> <?><?> <?><?><?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?> <?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?>
           <?><?><?> <?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?> <?><?><?><?><?> <?> <?><?><?><?><?> (conflicting)
           <?><?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?>. <?><?><?><?>
           <?><?><?><?>:

               [Unit]
               Description=My Surviving Service
               SurviveFinalKillSignal=yes
               IgnoreOnIsolate=yes
               DefaultDependencies=no
               After=basic.target
               Conflicts=reboot.target kexec.target poweroff.target halt.target rescue.target emergency.target
               Before=shutdown.target rescue.target emergency.target

               [Service]
               Type=oneshot
               ExecStart=sleep infinity

       o   <?><?><?><?><?> <?><?> <?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?>
           (templated units) <?><?> <?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?> <?><?><?><?> slice <?><?><?> <?><?><?>
           <?><?><?><?> <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?>
           <?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?> slice<?><?>
           <?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?> <?><?><?> <?><?>
           <?><?> <?><?><?><?> <?><?><?>
           <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?><?><?> <?><?><?> <?><?><?>. <?><?><?><?>
           <?><?><?><?><?> <?><?><?><?> <?><?> <?><?><?><?><?><?>
           foo@test.service<?> <?><?> <?><?><?><?> system-foo.slice
           <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?> <?><?><?>
           <?><?><?><?><?> <?><?><?>:

               [Unit]
               SurviveFinalKillSignal=yes
               IgnoreOnIsolate=yes
               DefaultDependencies=no

       o   <?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?> <?>
           <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
           <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?><?><?>
           <?><?> <?><?><?> <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?>
           <?><?><?><?><?><?><?> <?><?> <?><?><?><?><?> <?><?>
           <?><?><?><?><?><?><?><?> <?><?><?> <?><?><?><?><?> <?><?>
           <?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
           <?><?><?><?> <?><?><?><?><?><?>. (<?><?><?> <?><?><?> <?><?>
           <?><?><?><?> DefaultDependencies=no <?> <?><?> <?><?><?><?><?><?>
           <?><?> Conflicts=umount.target <?><?><?><?> <?><?><?><?><?><?>.)

       o   <?><?><?> <?><?><?><?> <?><?><?><?><?><?> <?><?> <?><?><?> D-Bus
           <?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?>
           <?><?> <?><?> soft-reboot <?><?><?><?><?><?> <?><?><?><?><?><?>
           <?><?><?> <?><?><?><?> <?><?><?><?><?><?><?> D-Bus <?><?><?><?><?>
           <?><?><?> <?> <?><?><?> <?><?><?><?><?><?>
           <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?>. <?><?><?><?><?>
           <?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?> sd-bus(3)
           <?><?><?> <?><?><?> <?><?> <?><?><?><?><?><?><?> <?><?>
           <?><?><?><?><?> <?><?><?><?> <?><?><?> <?><?> <?><?><?>
           <?><?><?><?>.

               /* SPDX-License-Identifier: MIT-0 */

               /* A D-Bus service that automatically reconnects when the system bus is
                * restarted.
                *
                * Compile with 'cc sd_bus_service_reconnect.c $(pkg-config --libs --cflags libsystemd)'
                *
                * To allow the program to take ownership of the name 'org.freedesktop.ReconnectExample',
                * add the following as /etc/dbus-1/system.d/org.freedesktop.ReconnectExample.conf
                * and then reload the broker with 'systemctl reload dbus':

               <?xml version="1.0"?> <!--*-nxml-*-->
               <!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
                 "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
               <busconfig>
                 <policy user="root">
                   <allow own="org.freedesktop.ReconnectExample"/>
                   <allow send_destination="org.freedesktop.ReconnectExample"/>
                   <allow receive_sender="org.freedesktop.ReconnectExample"/>
                 </policy>

                 <policy context="default">
                   <allow send_destination="org.freedesktop.ReconnectExample"/>
                   <allow receive_sender="org.freedesktop.ReconnectExample"/>
                 </policy>
               </busconfig>

                *
                * To get the property via busctl:
                *
                * $ busctl --user get-property org.freedesktop.ReconnectExample \
                *                              /org/freedesktop/ReconnectExample \
                *                              org.freedesktop.ReconnectExample \
                *                              Example
                * s "example"
                */

               #include <errno.h>
               #include <stdio.h>
               #include <stdlib.h>
               #include <systemd/sd-bus.h>

               #define _cleanup_(f) __attribute__((cleanup(f)))

               static int log_error(int r, const char *str) {
                 fprintf(stderr, "%s failed: %s\n", str, strerror(-r));
                 return r;
               }

               typedef struct object {
                 const char *example;
                 sd_bus **bus;
                 sd_event **event;
               } object;

               static int property_get(
                               sd_bus *bus,
                               const char *path,
                               const char *interface,
                               const char *property,
                               sd_bus_message *reply,
                               void *userdata,
                               sd_bus_error *error) {

                 object *o = userdata;

                 if (strcmp(property, "Example") == 0)
                   return sd_bus_message_append(reply, "s", o->example);

                 return sd_bus_error_setf(error,
                                          SD_BUS_ERROR_UNKNOWN_PROPERTY,
                                          "Unknown property '%s'",
                                          property);
               }

               /* https://www.freedesktop.org/software/systemd/man/sd_bus_add_object.html */
               static const sd_bus_vtable vtable[] = {
                 SD_BUS_VTABLE_START(0),
                 SD_BUS_PROPERTY(
                   "Example", "s",
                   property_get,
                   0,
                   SD_BUS_VTABLE_PROPERTY_CONST),
                 SD_BUS_VTABLE_END
               };

               static int setup(object *o);

               static int on_disconnect(sd_bus_message *message, void *userdata, sd_bus_error *ret_error) {
                 int r;

                 r = setup((object *)userdata);
                 if (r < 0) {
                   object *o = userdata;
                   r = sd_event_exit(*o->event, r);
                   if (r < 0)
                     return log_error(r, "sd_event_exit()");
                 }

                 return 1;
               }

               /* Ensure the event loop exits with a clear error if acquiring the well-known
                * service name fails */
               static int request_name_callback(sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
                 int r;

                 if (!sd_bus_message_is_method_error(m, NULL))
                   return 1;

                 const sd_bus_error *error = sd_bus_message_get_error(m);

                 if (sd_bus_error_has_names(error, SD_BUS_ERROR_TIMEOUT, SD_BUS_ERROR_NO_REPLY))
                   return 1; /* The bus is not available, try again later */

                 fprintf(stderr, "Failed to request name: %s\n", error->message);
                 object *o = userdata;
                 r = sd_event_exit(*o->event, -sd_bus_error_get_errno(error));
                 if (r < 0)
                   return log_error(r, "sd_event_exit()");

                 return 1;
               }

               static int setup(object *o) {
                 int r;

                 /* If we are reconnecting, then the bus object needs to be closed, detached
                  * from the event loop and recreated.
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_detach_event.html
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_close_unref.html
                  */
                 if (*o->bus) {
                   r = sd_bus_detach_event(*o->bus);
                   if (r < 0)
                     return log_error(r, "sd_bus_detach_event()");
                   *o->bus = sd_bus_close_unref(*o->bus);
                 }

                 /* Set up a new bus object for the system bus, configure it to wait for D-Bus
                  * to be available instead of failing if it is not, and start it. All the
                  * following operations are asynchronous and will not block waiting for D-Bus
                  * to be available.
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_new.html
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_set_address.html
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_set_bus_client.html
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_negotiate_creds.html
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_set_watch_bind.html
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_set_connected_signal.html
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_start.html
                  */
                 r = sd_bus_new(o->bus);
                 if (r < 0)
                   return log_error(r, "sd_bus_new()");
                 r = sd_bus_set_address(*o->bus, "unix:path=/run/dbus/system_bus_socket");
                 if (r < 0)
                   return log_error(r, "sd_bus_set_address()");
                 r = sd_bus_set_bus_client(*o->bus, 1);
                 if (r < 0)
                   return log_error(r, "sd_bus_set_bus_client()");
                 r = sd_bus_negotiate_creds(*o->bus, 1, SD_BUS_CREDS_UID|SD_BUS_CREDS_EUID|SD_BUS_CREDS_EFFECTIVE_CAPS);
                 if (r < 0)
                   return log_error(r, "sd_bus_negotiate_creds()");
                 r = sd_bus_set_watch_bind(*o->bus, 1);
                 if (r < 0)
                   return log_error(r, "sd_bus_set_watch_bind()");
                 r = sd_bus_start(*o->bus);
                 if (r < 0)
                   return log_error(r, "sd_bus_start()");

                 /* Publish an interface on the bus, specifying our well-known object access
                  * path and public interface name.
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_add_object.html
                  * https://dbus.freedesktop.org/doc/dbus-tutorial.html
                  */
                 r = sd_bus_add_object_vtable(*o->bus,
                                              NULL,
                                              "/org/freedesktop/ReconnectExample",
                                              "org.freedesktop.ReconnectExample",
                                              vtable,
                                              o);
                 if (r < 0)
                   return log_error(r, "sd_bus_add_object_vtable()");
                 /* By default, the service is only assigned an ephemeral name. Also add a
                  * well-known one, so that clients know whom to call. This needs to be
                  * asynchronous, as D-Bus might not be yet available. The callback will check
                  * whether the error is expected or not, in case it fails.
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_request_name.html
                  */
                 r = sd_bus_request_name_async(*o->bus,
                                               NULL,
                                               "org.freedesktop.ReconnectExample",
                                               0,
                                               request_name_callback,
                                               o);
                 if (r < 0)
                   return log_error(r, "sd_bus_request_name_async()");
                 /* When D-Bus is disconnected this callback will be invoked, which will set up
                  * the connection again. This needs to be asynchronous, as D-Bus might not yet
                  * be available.
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_match_signal_async.html
                  */
                 r = sd_bus_match_signal_async(*o->bus,
                                               NULL,
                                               "org.freedesktop.DBus.Local",
                                               NULL,
                                               "org.freedesktop.DBus.Local",
                                               "Disconnected",
                                               on_disconnect,
                                               NULL,
                                               o);
                 if (r < 0)
                   return log_error(r, "sd_bus_match_signal_async()");
                 /* Attach the bus object to the event loop so that calls and signals are
                  * processed.
                  * https://www.freedesktop.org/software/systemd/man/sd_bus_attach_event.html
                  */
                 r = sd_bus_attach_event(*o->bus, *o->event, 0);
                 if (r < 0)
                   return log_error(r, "sd_bus_attach_event()");

                 return 0;
               }

               int main(int argc, char **argv) {
                 /* The bus should be relinquished before the program terminates. The cleanup
                  * attribute allows us to do it nicely and cleanly whenever we exit the block.
                  */
                 _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
                 _cleanup_(sd_event_unrefp) sd_event *event = NULL;
                 object o = {
                   .example = "example",
                   .bus = &bus,
                   .event = &event,
                 };
                 int r;

                 /* Create an event loop data structure, with default parameters.
                  * https://www.freedesktop.org/software/systemd/man/sd_event_default.html
                  */
                 r = sd_event_default(&event);
                 if (r < 0)
                   return log_error(r, "sd_event_default()");

                 /* By default, the event loop will terminate when all sources have disappeared,
                  * so we have to keep it 'occupied'. Register signal handling to do so.
                  * https://www.freedesktop.org/software/systemd/man/sd_event_add_signal.html
                  */
                 r = sd_event_add_signal(event, NULL, SIGINT|SD_EVENT_SIGNAL_PROCMASK, NULL, NULL);
                 if (r < 0)
                   return log_error(r, "sd_event_add_signal(SIGINT)");

                 r = sd_event_add_signal(event, NULL, SIGTERM|SD_EVENT_SIGNAL_PROCMASK, NULL, NULL);
                 if (r < 0)
                   return log_error(r, "sd_event_add_signal(SIGTERM)");

                 r = setup(&o);
                 if (r < 0)
                   return EXIT_FAILURE;

                 /* Enter the main loop, it will exit only on sigint/sigterm.
                  * https://www.freedesktop.org/software/systemd/man/sd_event_loop.html
                  */
                 r = sd_event_loop(event);
                 if (r < 0)
                   return log_error(r, "sd_event_loop()");

                 /* https://www.freedesktop.org/software/systemd/man/sd_bus_release_name.html */
                 r = sd_bus_release_name(bus, "org.freedesktop.ReconnectExample");
                 if (r < 0)
                   return log_error(r, "sd_bus_release_name()");

                 return 0;
               }


       <?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?>
       <?><?> <?><?><?><?><?> <?><?><?><?> <?><?> <?><?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?>
       <?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?>
       <?><?><?> <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?> <?>
       <?><?> <?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?>
       <?><?><?><?> <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?> <?><?><?> <?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?> <?><?><?><?><?><?><?><?><?>
       <?><?><?><?> <?><?><?> <?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?>.
       <?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?> <?><?>
       <?><?><?><?> <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?> <?><?><?> <?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?> <?><?><?> <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?>
       <?><?><?> <?><?><?> <?><?><?><?> <?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?>
       <?><?><?><?> <?><?><?><?><?><?> <?><?><?><?> <?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?> <?><?><?><?><?> <?><?> (<?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?> <?><?> <?><?> <?><?> <?><?><?><?> <?><?><?><?><?>)
       <?><?><?><?><?> (pin) <?><?><?><?><?><?><?><?> <?> <?><?>
       <?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?> (<?><?><?> <?><?> <?><?><?><?> <?><?><?> <?><?>
       <?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?><?><?>/<?><?><?><?><?><?>/<?><?><?><?><?>
       <?><?><?><?> <?><?> <?><?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?>). <?><?> <?><?><?> <?><?><?><?> <?><?><?><?>
       <?><?><?><?><?><?> <?><?><?><?><?><?><?><?> <?><?> <?><?><?> <?><?>
       <?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
       <?><?><?> <?><?><?><?><?><?> <?><?><?> <?><?><?><?><?> <?><?><?><?> <?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?> <?><?>
       <?><?><?><?><?> <?><?><?><?><?><?> IPC <?> <?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>. <?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?>
       <?><?><?><?><?><?><?> <?><?> <?><?><?> <?><?><?><?> <?><?><?><?><?>
       Portable Services[1] <?><?><?><?> <?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?> <?><?><?><?> <?><?> <?><?><?> <?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?> <?><?> <?><?><?><?> BindPaths= <?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?> <?><?><?><?><?>
       <?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?> <?><?><?> <?><?><?><?>
       <?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> <?> <?><?><?><?> <?><?>
       <?><?><?><?><?> <?><?> <?><?><?><?> <?><?> <?><?><?> <?><?><?><?>
       <?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?>
       <?><?><?><?>.

<?><?><?><?> (NOTES)
       <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?> <?><?><?><?>
       <?><?> systemd-shutdown(8) <?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?> <?><?>
       /usr/lib/systemd/system-shutdown/ <?><?><?> <?><?><?><?>
       <?><?><?><?><?><?><?> <?><?>.

       <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?> <?><?>
       systemd-soft-reboot.service (<?> <?><?><?><?><?><?><?> <?><?><?><?><?>)
       <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?> <?><?><?><?>. <?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?>
       <?><?><?><?><?><?> <?><?><?><?><?> systemctl soft-reboot <?><?><?><?>
       <?><?><?><?>.

       <?><?><?><?> <?><?><?><?><?> <?><?><?><?><?> <?><?> <?><?><?> <?><?>
       <?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> <?><?><?><?> <?><?>
       "/run/nextroot/" <?><?><?><?><?><?><?><?><?><?> <?><?><?>
       <?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?> <?><?><?><?><?> reboot
       <?><?> <?><?><?><?><?><?> soft-reboot <?><?><?><?><?> <?><?><?><?><?>
       <?><?>.

<?><?><?><?><?><?> <?><?><?><?><?><?> (SEE ALSO)
       systemd(1), systemctl(1), systemd.special(7), systemd-
       poweroff.service(8), systemd-suspend.service(8), bootup(7)

<?><?><?><?> (NOTES)
        1. Portable Services
           https://systemd.io/PORTABLE_SERVICES

systemd 261.2                                   SYSTEMD-SOFT-REBOOT.SERVICE(8)