ACSE/Presentation and ROSE Interface Programmer's Guide

Chapter 3 35

Using ACSE/Presentation

Step 2: Establish an Association

Establish Initiator and Responder Roles

Process A and Process B establish initiator and responder roles using the

attribute, AP_ROLE_ALLOWED in a call to ap_set_env(). In this

example, Process A is the initiator, and Process B is the responder. (See

Figure 3-3.)

Figure 3-3 Establish Roles

NOTE The initiator and responder roles must be established before binding the

communication endpoint to the local presentation address while in the

AP_UNBOUND state. Any change in AP_ROLE_ALLOWED after

binding is ignored.

Binding the Endpoints

Process A and Process B must each bind a valid presentation address (p-

selector, s-selector, t-selector, and NSAP) to its endpoint by using the

attribute AP_BIND_PADDR in the ap_set_env() call. (See Figure 3-4.)

For more information on presentation addresses, refer to Chapter 4.

Communication

Endpoint A

Endpoint B

Process A

Process B

AP Environment A AP Environment B

ap_set_env()

Responder

Initiator

AP_ROLE_ALLOWED,initiator

AP_ROLE_ALLOWED,responder