Microsoft Logparser allows you to analyze log files in a generic SQL way. You can analyze your own log files, and even binary log files. For the latter, you need to provide a com object implementing an interface so that the Logparser can read your binary log file.

However, it looks like there is a compatibility issue with Windows 2000 (I’m running the service pack 4). When declaring TIMESTAMP fields or integer fileds, and initializing the variant object in the GetValue method with the V_I8 or V_DATE values, Logparser gives a « Error retrieving field: Bad variable type ».

Using the same version of Logparser (2.2.10) and the same COM DLL on a XP or a 2003 Server machine, everything works fine…

Any clue for a solution ?

Nicolas Riousset

Président et fondateur de NeoLegal, développe des solutions logicielles qui facilitent le quotidien des professionnels du droit des sociétés.

nicolas.riousset.com

UUID are unique identifiers which are used, for example, to identify COM objects.

To generate a new UUID, use the command line tool « uuidgen.exe ».

Nicolas Riousset

Président et fondateur de NeoLegal, développe des solutions logicielles qui facilitent le quotidien des professionnels du droit des sociétés.

nicolas.riousset.com

Different problems can cause this error.

It is often related to the settings of your projects. If you use different run-time libraries for your main program and for your libraries/DLLs, they will not allocate and deallocate memory in the same way. Consequently, if some memory allocated by a library is released by another one, you may get this kind of error.
You can check your projects settings in : project->settings->C++->Code generation->Use run-time library.

However, the explanation can be really simpler. Just try to delete two times a same object, and you may get this error. To ensure that an object is not deleted twice, just put a breakpoint in its destructor.
I encountered this problem after doing a stupid mistake. I declared a CWinThread m_thread member variable in a class CMyClass I forgot that its m_bAutoDelete member variable is set to TRUE by default. Logically, m_thread was deleting itself once it was terminated. And of course, the destructor of CMyClass was trying to delete m_thread too… BOOM !!!

Nicolas Riousset

Président et fondateur de NeoLegal, développe des solutions logicielles qui facilitent le quotidien des professionnels du droit des sociétés.

nicolas.riousset.com

In some cases, you may need to convert a unicode string into an ANSI C null-terminated string. The WideCharToMultiByte function allows you to do this.

In the following example, I have used the ReadDirectoryChangesW function to detect a file modification in a directory. The name of the modified file is stored in UNICODE format. I want to convert it to  a standard C string.

PFILE_NOTIFY_INFORMATION pstFileNotif;
…
// Initialization of pstFileNotif
…

char szNotifFilename[ MAX_PATH ] = { 0 };
int iNbChar = WideCharToMultiByte(
CP_OEMCP,
NULL,
pstFileNotif->FileName,
pstFileNotif->FileNameLength / sizeof( WCHAR ),
szNotifFilename,
sizeof( szNotifFilename ) / sizeof( char ),
NULL, NULL ) ;

if ( iNbCar == 0 )
{
// Error
}

Be careful : the size of the 2 strings is not their length in bytes, but their length in characters (a UNICODE character takes 2 bytes)

Nicolas Riousset

Président et fondateur de NeoLegal, développe des solutions logicielles qui facilitent le quotidien des professionnels du droit des sociétés.

nicolas.riousset.com