Calling CONVERT Before RECEIVE_ALLOCATE May Lead to Event 60

• Microsoft SNA Server, versions 3.0, 3.0 SP1, 3.0 SP2

SYMPTOMS

If WinAPPCStartup() is not included at the beginning of a Windows-based invokable transaction program, and if the TP first calls the CONVERT API, the TP's call to RECEIVE_ALLOCATE may subsequently stop (hang) and not complete.

CAUSE

By first calling the CONVERT API prior to calling RECEIVE_ALLOCATE, the SNA client APPC interface was being confused, causing it to fail to properly match the incoming attach request to the application's RECEIVE_ALLOCATE call. If a Windows-based transaction program does not begin with WinAPPCStartup(), SNA Server automatically calls WinAPPCStartup() when the application calls the first APPC function. However, if this call is preceded by a Common Service Verb function (such as CONVERT), this can confuse the APPC interface.

WORKAROUND

The application can work around this problem by explicitly calling WinAPPCStartup prior to calling any Common Service Verb functions.

STATUS

Microsoft has confirmed this to be a problem in SNA Server versions 3.0, 3.0 Service Pack 1 (SP1), and 3.0 SP2. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

Additional query words: APPC invokable TP WinAPPCStartup

Keywords : prodsna snaappc snaprog snatp
Version : WINDOWS:3.0,3.0 SP1,3.0 SP2
Platform : WINDOWS
Issue type : kbbug