Request primitives are received by the signaling process using the sl_receive_request() subroutine. They are sent from the software components listed above requesting that some action be taken by the signaling process. A confirm primitive indicating the result of that action must always be returned to the sender of the request. The only deviation from this is the SL_ABORT_REQ, when the confirm pertains to the previous command indicated in the iCommandNo field of the ABORT_REQUEST_ST.