IPP_SET_JOB_ATTRIBUTES

[vladimir]

How can I change parameters of the Job?
I try to use the following code, but something wrong with it:
//Change user defined "HISTORY" attribute
    request = ippNewRequest(IPP_SET_JOB_ATTRIBUTES);

    ippAddString(request, IPP_TAG_OPERATION, IPP_TAG_URI, "job-uri",
                   NULL, "ipp://localhost/jobs/3");
    ippAddString(request,IPP_TAG_OPERATION, IPP_TAG_NAME,"HISTORY",NULL, "new_value");

//Do request
    ippDelete(cupsDoRequest(http, request, "/jobs/3"));
    printf ("ERROR %s<BR>",cupsLastErrorString());
////////////////////////////////////////////////////////////
cupsDoRequest returns Ok,but the parameter does not change.
Something wrong with my code or it's future is not implemented in this way?