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jreutter's avatar
jreutter
New Contributor
12 years ago

DLL interface handling TC6 vs. TC9

Currently we use TC6 and we evaluate if we upgrade to TC9.

(TC6.51.405.5 <-> TC9.20.2460.7 Trial version)

My environment is still the same.

In TC6 following code works:



sub test


  (dim all var)



  G_sAssistBasePath = "C:\Program Files\Motion Suite\CntStudio\"



  Set Def_DLL = DLL.DefineDLL("AssistBase")

  Set Lib = DLL.Load(G_sAssistBasePath + "AssistBase.dll")

  Def_DLL.DefineProc "ExecuteCmdLine", vt_lpstr, vt_lpstr, vt_int

  Def_DLL.DefineProc "GetErrorLine", vt_int, vt_lpstr, vt_int

  Set LpRet = DLL.New("LPWSTR", 1024)

  Set LpCmd = DLL.New("LPWSTR", 1024)

  LpCmd.Text = "NewAssist"

 

  bRet = Lib.ExecuteCmdLine(LpCmd, LpRet) 

end sub



TC9 creates an exception during "Lib.ExecuteCmdLine(LpCmd, LpRet) "

--> An exception occurred: 0xC0000005; class: ; description: ''



Is there a change? Do I need to change something?

Thanks


  • AlexanderM's avatar
    AlexanderM
    Icon for Staff rankStaff
    12 years ago

    Hi JayR,


     


    TestComplete requires that the exported functions match the stdcall calling convention, you can see this requirement in the Calling DLL Functions From Tests - Known Limitations help topic.


     


    Explicitly specifying the calling convention solves the problem:


     


    ASSIST_EXT_CLASS INT _stdcall ExecuteCmdLine( LPCTSTR lpCommand, LPTSTR lpOutput)


     


    The strange thing is that this limitation was always there, so I am not sure why it worked in version 6.51. However, explicitly setting the convention should not harm TC 6.51 tests anyway.