Immediate CMRCV Response Also Trace the Buffer

• Microsoft SNA Server, version 2.11 SP1
  on the following platforms: NT

SYMPTOMS

When a CMRCV call is being posted asynchronously the immediate CMRCV response (which returns with CM_OPERATION_INCOMPLETE) is also tracing the buffer.

CAUSE

If you are writing a CPI-C application, you can define whether you like to use a blocking or nonblocking conversation. In case of a blocking operation, a call will be returned when the requested operation is complete (synchronous call). In the case of a nonblocking call, the call will be returned immediately after the operation is initiated (asynchronous call).

In a CPI-C application this can be done using the CPI-C API call Set_Processing_Mode (cmspm) where you can specify the receive Types as CM_BLOCKING or CM_NON_BLOCKING. This indicates that all subsequent calls will be returned either synchronous or asynchronous, accordingly.

If you are using asynchronous calls the receive request call, CMRCV will return immediately with a CMRECV response with CM_INCOMPLETE_DATA_RECEIVED. Although the data returned is not complete, the SNA Trace utility is tracing that buffer. This might be confusing when you analyze the CPI-C API traces.

With the SNA Applications: CPI-C trace enabled, you may see the following:

CPIC   CMRCV request
CPIC    Conversation ID = 01000000
CPIC    Requested length = 4096
CPIC   Conversation characteristics
CPIC    Conversation type = CM_MAPPED_CONVERSATION
CPIC    Fill type = CM_FILL_LL
CPIC    Receive type = CM_RECEIVE_AND_WAIT
CPIC   ---------------------------------------------- 13:34:40.23
CPIC   CMRCV response, result = CM_OPERATION_INCOMPLETE
CPIC   ---- Buffer at address 002F27A0 ----
CPIC   B8002F00 B8002F00 00000000 00000000     <../.../.........>
CPIC   00000000 00000000 00000000 00000000     <................>
CPIC   00000000 00000000 00000000 00000000     <................>
CPIC   00000000 00000000 00000000 00000000     <................>
CPIC   00000000 00000000 00000000 00000000     <................>
CPIC    Data received type = CM_NO_DATA_RECEIVED
CPIC    Received length = 6625328
CPIC    Status received = ***UNKNOWN STATUS_RECEIVED***
CPIC    Request to send received = ***UNKNOWN REQ_TO_SEND TYPE*** 

STATUS

Microsoft has confirmed this to be a problem in Microsoft SNA Server version 2.11 and 2.11.sp1. This problem was corrected in the latest Microsoft SNA Server 2.11 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

Additional query words: prodsna SP1 CPI-C CMRCV

Keywords : kbprg snaprog kbbug2.11 kbbug2.11.sp1 kbfix2.11.sp2
Version : WINDOWS:2.11 SP1
Platform : WINDOWS
Issue type :