Multiple SLI_OPEN()s Can Cause SESSION_ALREADY_OPEN

ID: Q150513

The information in this article applies to:

Microsoft SNA Server, versions 2.0, 2.1, 2.11, 2.11 SP1
on the following platforms: NT

SYMPTOMS

When a multi-threaded LUA application issues more than one SLI_OPEN() before the first SLI_OPEN() returns, the result is the following:


SLI_OPEN response
   UNSUCCESSFUL - SESSION_ALREADY_OPEN

   primary return code:   0014      (LUA_UNSUCCESSFUL)
   secondary return code: 00000035  (LUA_SESSION_ALREADY_OPEN)

This SLI_OPEN response will contain an LUA_luname that had not been opened using an SLI_OPEN().

NOTE: The LUA_luname field is part of the VCB (verb control block) for the SLI_OPEN() and is explained in the SNA Server [ASCII 147]Programmer's Reference[ASCII 148] on page 88.

CAUSE

There is a problem in the SNA Server SLI library's algorithm to match up an SLI application VCB with its owning session control block. This can cause the SLI library to complete the wrong SLI call if two SLI_OPENs are pending at the same time.

RESOLUTION

A update to the SNA Server SLI interface corrects this problem by properly matching the SLI application's verb control block with the correct session control block.

STATUS

Microsoft has confirmed this to be a problem in Microsoft SNA Server versions 2.0, 2.10, 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:

Keywords : kbenv ntprotocol kbbug2.00 kbbug2.10 kbbug2.11 kbbug2.11.sp1 ntsna
Version : WINDOWS:2.0,2.1,2.11,2.11 SP1
Platform : WINDOWS
Issue type :