подготовьте сообщение D-Bus к передаче  (Prepare a D-Bus message for transmission)
  
Имя (Name)
sd_bus_message_seal - Prepare a D-Bus message for transmission
Синопсис (Synopsis)
#include <systemd/sd-bus.h>
       int sd_bus_message_seal(sd_bus_message *m, uint64_t cookie,
                               uint64_t timeout_usec);
Описание (Description)
sd_bus_message_seal() finishes the message m and prepares it for
       transmission using sd_bus_send(3).  cookie specifies the
       identifier used to match the message reply to its corresponding
       request.  timeout_usec specifies the maximum time in microseconds
       to wait for a reply to arrive.
       Note that in most scenarios, it's not necessary to call this
       function directly.  sd_bus_call(3), sd_bus_call_async(3) and
       sd_bus_send(3) will seal any given messages if they have not been
       sealed yet.
Возвращаемое значение (Return value)
On success, this function returns a non-negative integer. On
       failure, it returns a negative errno-style error code.
   Errors
       Returned errors may indicate the following problems:
       -EINVAL
           The m parameter is NULL.
       -EBADMSG
           The D-Bus message m has open containers.
       -ENOMSG
           The D-Bus message m is a reply but its type signature does
           not match the return type signature of its corresponding
           member in the object vtable.
Примечание (Note)
These APIs are implemented as a shared library, which can be
       compiled and linked to with the libsystemd pkg-config(1) file.
Смотри также (See also)
systemd(1), sd-bus(3), sd_bus_call(3), sd_bus_call_async(3),
       sd_bus_send(3)