Calling Error_Extract for an Unestablished Conversation
If APPC/MVS cannot establish a conversation, APPC/MVS still assigns a conversation
ID to the request to allocate the conversation. Your TP can use that conversation
ID as input to Error_Extract when errors occur in calls to the following services:
- LU 6.2 Allocate
- LU 6.2 Get_Conversation
- CPI-C Initialize_Conversation
- CPI-C Accept_Conversation.
For example, say that two programs call the LU 6.2 Allocate service from the same address space and both calls to Allocate receive error return codes. APPC/MVS assigns a different conversation ID to each call. Your TP can specify either of those conversation IDs on calls to Error_Extract, even though the conversations were never actually allocated.
If APPC/MVS is not active, your TP will not be able to establish a conversation. In this case, your TP receives decimal return code 20 (product-specific error) from the Allocate call. To verify that APPC/MVS is not active, call Error_Extract, which returns decimal return code 64 when APPC/MVS is not active. (To debug other product-specific errors, refer to Diagnosing Product-Specific Errors.)