HP A4500A - VMEbus Single Board Computer 744 Motherboard Programmer's Manual page 39

Process B can reject the connection if the proposed transfer syntax is not
supported by setting the res field in structure ap_cdrl_t to USER_REJ or
PROV_REJ and prov_rsn is the reason for the reject. If the process
cannot accept the association request for other reasons, the process sets
the reason using the A_ASSOC_RSP primitive.
Figure 3-7 Confirm Association
Chapter 3
Process A
AP Environment A
ap_poll()
Initiator
Communication
Endpoint A
Step 2: Establish an Association
Process B
ap_rcv()
AP Environment B
ap_get_env()
AP_PCDL,pcdl
ap_set_env()
AP_PCDRL.pcdrl
Responder
ap_snd()
Communication
Endpoint B
request assoc.
(listening)
Using ACSE/Presentation
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