PRL_RESULT RegisterExistingVM(PRL_HANDLE hServer, PRL_CONST_STR sVmDirectory)
{
    PRL_HANDLE hJob = PRL_INVALID_HANDLE;
    PRL_HANDLE hJobResult = PRL_INVALID_HANDLE;

    PRL_RESULT ret = PRL_ERR_UNINITIALIZED;
    PRL_RESULT nJobRetCode = PRL_ERR_UNINITIALIZED;

    // Register the virtual machine with the Virtuozzo Service.
    hJob = PrlSrv_RegisterVm(
        hServer,
        sVmDirectory,
        PRL_TRUE);  // Using non-interactive mode.

    ret = PrlJob_Wait(hJob, 10000);

    // Check the return code of PrlSrv_RegisterVm.
    PrlJob_GetRetCode(hJob, &nJobRetCode);
    if (PRL_FAILED(nJobRetCode))
    {
        printf("PrlSrv_RegisterVm returned error: %s\n",
            prl_result_to_string(nJobRetCode));
        PrlHandle_Free(hJob);
        return -1;
    }

    // Obtain the virtual machine handle from the job object.
    // We will use the handle later to modify the virtual machine
    // configuration.
    PRL_HANDLE hVm = PRL_INVALID_HANDLE;
    ret = PrlJob_GetResult(hJob, &hJobResult);
    if (PRL_FAILED(ret))
    {
        // Handle the error...
        return ret;
    }

    ret = PrlResult_GetParam(hJobResult, &hVm);
    if (PRL_FAILED(ret))
    {
        // Handle the error...
        return ret;
    }

    PrlHandle_Free(hJob);
    PrlHandle_Free(hJobResult);

    printf("Virtual machine '%s' was successfully registered.",
            sVmDirectory);

    // The following code will generate and set a new MAC address
    // for every virtual network adapter that exists in the virtual machine.
    // This step is optional and should normally be performed when the virtual
    // machine is a copy of another virtual machine.

    PRL_HANDLE hJobBeginEdit;
    PRL_HANDLE hJobCommit;

    // Begin the virtual machine editing operation.
    hJobBeginEdit = PrlVm_BeginEdit(hVm);
    ret = PrlJob_Wait(hJobBeginEdit, 10000);
    PrlJob_GetRetCode(hJobBeginEdit, &nJobRetCode);
    if (PRL_FAILED(nJobRetCode))
    {
        fprintf(stderr, "Error: %s\n", prl_result_to_string(nJobRetCode));
        PrlHandle_Free(hJobBeginEdit);
        return nJobRetCode;
    }

    // Obtain a handle of type PHT_VM_CONFIGURATION containing the
    // virtual machine configuration data.
    PRL_HANDLE hVmCfg = PRL_INVALID_HANDLE;
    ret = PrlVm_GetConfig(hVm, &hVmCfg);
    if (PRL_FAILED(ret))
    {
        // Handle the error...
        return ret;
    }

    // Determine the number of the network adapters
    // installed in the machine.
    PRL_UINT32 nCount = PRL_ERR_UNINITIALIZED;
    ret = PrlVmCfg_GetNetAdaptersCount(hVmCfg, &nCount);
    if (PRL_FAILED(ret))
    {
        // Handle the error...
        return ret;
    }

    // Itereate through the adapter list.
    PRL_HANDLE hNetAdapter = PRL_INVALID_HANDLE;
    for (PRL_UINT32 i = 0; i < nCount; ++i)
    {
        ret = PrlVmCfg_GetNetAdapter(hVmCfg, i, &hNetAdapter);
        if (PRL_FAILED(ret))
        {
            // Handle the error...
            return ret;
        }

        // Automatically generate new MAC address for the current adapter.
        // The address will be updated in the configuration object.
        ret = PrlVmDevNet_GenerateMacAddr(hNetAdapter);
        if (PRL_FAILED(ret))
        {
            // Handle the error...
            return ret;
        }
    }

    // Commit the changes to the virtual machine.
    hJobCommit = PrlVm_Commit(hVm);

    // Check the results of the commit operation.
    ret = PrlJob_Wait(hJobCommit, 10000);
    PrlJob_GetRetCode(hJobCommit, &nJobRetCode);
    if (PRL_FAILED(nJobRetCode))
    {
        fprintf(stderr, "Commit error: %s\n", prl_result_to_string(nJobRetCode));
        PrlHandle_Free(hJobCommit);
        return nJobRetCode;
    }

    PrlHandle_Free(hNetAdapter);
    PrlHandle_Free(hVm);
    PrlHandle_Free(hVmCfg);
    PrlHandle_Free(hJobCommit);
    PrlHandle_Free(hJobBeginEdit);

    return 0;
}