if (file.open(pszFileName))
   {
                        pby = (char*)file.getBufferPointer();
#if FOR_LAB
   DWORD dwSize = file.getFileSize();
   DWORD dwMinFileSize = sizeof(CVTableCfgFileHeader) +
            sizeof(CVTableCfgFileFracHdr) + sizeof(CVTableCfgFileSigDesc);
      if (dwSize < dwMinFileSize)
      {
         Error.Log(__FILE__, "CVT config file %s is too short.", pszFileName);
         return false;     // need at least one signal description to be useful
      }
#endif

      pFileHdr = (CVTableCfgFileHeader*)pby;
      pby += sizeof(CVTableCfgFileHeader);
#if FOR_LAB
      if (strcmp(pFileHdr->szSignature, "CVT-CFG") != 0)
      {
         Error.Log(__FILE__, "CVT cfg file %s has wrong signature.", pszFileName);
         return false;
      }
      if (pFileHdr->version != iCVTCFGVERSION)
      {
         Error.Log(__FILE__, "Wrong version of CVT cfg. Found %d expecting %d in %s",
            pFileHdr->version, iCVTCFGVERSION, pszFileName);
         return false;
      }
      if (pFileHdr->iNumFrac > CVTableIndex::iMAX_FRACTIONS)
      {
         Error.Log(__FILE__, "CVT cfg file %s has too many fractions", pszFileName);
         return false;
      }
#endif
         // --- ok... ready to build the whole table ---

   CVTableIndex *pIdx = m_hTblIdx.Init(CVTableIndex::pszTBLIDXNAME, 
                                       SharedMemObjHandle<CVTableIndex>::omCREATE_RO);
#if FOR_LAB
      if (pIdx == NULL)
      {
         Error.Log(__FILE__, "Unable to create CVT table index.");
         return false;
      }
#endif

   int iTotalSignalCt = 0;
      for (int iFrac=0; iFrac < pFileHdr->iNumFrac; ++iFrac)
      {
         pFracHdr = (CVTableCfgFileFracHdr*)pby;
         pby += sizeof(CVTableCfgFileFracHdr);

#if FOR_LAB
         if (*pFracHdr->szFracName == 0 ||
              pFracHdr->iNumSigs > 5000    )
         {
            Error.Log(__FILE__, "CVT cfg file '%s' fraction header %d malformed.", 
                      pszFileName, iFrac);
            break;
         }
#endif