RECEIVE processing using HPDT

This section summarizes the process for receiving normal application data using HPDT (see Figure 1).

  1. The application builds an XBUFLST-receive vector as described in Passing HPDT receive requirements to VTAM.
  2. The application issues an APPCCMD CONTROL=RECEIVE. The AREA parameter specifies an area for VTAM® to build a buffer list that points to data in CSM storage.
  3. After data is read from subchannel to CSM storage, VTAM transfers ownership of buffers to the application and builds the extended buffer list in the application's area.
  4. When the receive is posted complete, the application examines the extended buffer list in the address indicated by the AREA parameter. Each buffer list entry contains information used to address the data. The buffer list entries are mapped as shown in Using the extended buffer list (XBUFLST).
  5. The application returns all storage to CSM after the application has finished processing the data. See Receive macroinstruction completion considerations for complete information about the applications options.
Figure 1. RECEIVE processing using CSM buffers
Diagram that explains how an application uses the CSM buffers to receive data.
Parent topic: Receiving data using HPDT