RUI_PURGE & SLI_PURGE Verbs Fail When Using the Thunking DLLs

• Microsoft SNA Server for Windows NT, versions 2.11 and 2.11.sp1

SYMPTOMS

The 16-bit Windows LUA RUI_PURGE and SLI_PURGE calls fail when you run over the SNA Server Windows NT thunking DLLs.

CAUSE

The thunking library runs on a Win32 system in the Win16 VDM. When it receives an RUI call from a Win16 application, it allocates a new Verb Control Block (VCB) and copies all the entries from the original VCB into it. It does this because the packing of the VCBs are different for Win16 and Win32. It then passes the new VCB into the Win32 RUI library, which processes the verb.

The RUI_PURGE call has as one of its parameters the address of the VCB for the RUI_READ that is to be canceled. The thunking library, when it receives an RUI_PURGE verb, allocates a new VCB for the RUI_PURGE with Win32 packing, copies the entries from the original VCB into it and passes that into the Win32 RUI library to be processed. The new VCB that is passed into the library still has as its parameter the address of the old RUI_READ VCB. The Win32 library completely fails to recognize this address (it has only seen the address of the new VCB), and so returns the RUI_PURGE verb with an error.

RESOLUTION

The RUI thunking library has been changed to allow the new VCB for the RUI_PURGE to pass in the address of the new VCB for the RUI_READ, not the old VCB for the RUI_READ. The following files have been updated:

   <snaroot>\SYSTEM\THUNK\WINRUI.DLL
   <snaroot>\SYSTEM\THUNK\WINSLI.DLL

STATUS

Microsoft has confirmed this to be a problem in SNA Server versions 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