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  · DriverStudio          Distinguishing Windows 98 from NT in WDM Drivers
  · DriverBundle
  · Previews              WDM drivers run unchanged on both Windows NT 5.0 and on Windows 98. This is one
  · Compatibility         of the key benefits of WDM, but there may be cases where a driver needs to
 [Downloads]  ·           behave differently on the two platforms. Since there is no documented service at
                          kernel level that reports the identity of the platform, this could present a
 Wizards                  problem for driver developers.
  · Utilities
  · NT source             The system registry provides a solution. We suggest checking for the presence of
 examples                 key \Registry\Machine\SAM. If the key is present, it is safe to assume that the
  · VxD source            system is Windows NT. The key relates to the Security Accounts Manager, and so
 examples                 should never be present on a Windows 98 system. One might naively think that key
  · WDM source            \Registry\Machine\Software\Microsoft\Windows NT would provide a good test for an
 examples                 NT system, but in fact this key appears on many Windows 98 systems.
 [Resources]  ·
 Technical papers         Here's the code to check for the existence of \Registry\Machine\SAM if you are
  · Useful links          using the DDK:
  · Technical tips
 [Support]  ·             BOOLEAN RunningOnNT(void)
                          {
 Support                          OBJECT_ATTRIBUTES oa;
  · Knowledge base                UNICODE_STRING sam;
  · Problem                       HANDLE hKey;
 submission                       NTSTATUS status;
  · Product
 registration                     RtlInitUnicodeString(&sam, L"\\Registry\\Machine\\SAM");
  · Release notes
 [Shop NuMega]  ·                 InitializeObjectAttributes(&oa, &sam, OBJ_CASE_INSENSITIVE, NULL, NULL);
 Buy it!
  · Price list                    status = ZwOpenKey(&hKey, 0, &oa);
  · How to buy
  · Sales offices                 if ( NT_SUCCESS(status) )
                                  {
                                          ZwClose(hKey);
 [Y2K Compliance]                         return TRUE;
                                  }
                                  else
 [More information]                       return FALSE;
                          }

                          In DriverWorks version 2.0, a driver can simply check the global BOOLEAN
                          _bWindows98_, which is TRUE when running on a Windows 98 system.

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