TEST_RTS_AND_POST Does Not Work When Using WinAsyncAppc Call

• Microsoft SNA Server, versions 3.0 SP1, 3.0 SP2, 3.0 SP3, 4.0, 4.0 SP1

SYMPTOMS

The APPC/CPI-C command TEST_RTS_AND_POST does not work when using a WinAsyncAppc call. If the TEST_RTS_AND_POST verb is called asynchronously, the APPC library signals the completion of the event but never receives the post event.

CAUSE

TEST_RTS_AND_POST is one of the set of "post" APPC verbs which completes twice.

The TEST_RTS_AND_POST verb contains a post event. When the APPC library receives the verb, it makes a note of this post event, and then completes the verb immediately in the normal way, either by returning control to the application (if called synchronously) or by signaling a completion event which has also been supplied with the verb (if called asynchronously). Note that the completion event is different from the post event which the verb contained.

This is the first completion for the verb.

Later, if the APPC library gets a change direction message from the SNA Server service, it signals the post event.

This is the second completion of the verb.

The problem is that if the verb is called asynchronously, the APPC library signals the first completion correctly, but for the second completion it signals the completion event again, rather than the post event.

An application written to wait for the completion of the post event waits forever, and the application thinks that a change direction message has never been received by the APPC library.

RESOLUTION

Microsoft has confirmed this to be a problem in SNA Server versions 3.0, 3.0 SP1, 3.0 SP2, 3.0 SP3, 4.0, and 4.0 SP1. We are researching this problem in SNA Server version 3.0 and will post more information here in the Knowledge Base as it becomes available.

This problem was corrected in the latest SNA Server version 4.0 U.S. Service Pack. For information on obtaining this 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:

Keywords :
Version : WINDOWS:3.0 SP1,3.0 SP2,3.0 SP3,4.0,4.0 SP1
Platform : WINDOWS
Issue type : kbbug