kuttiam wrote: without any coclass. kuttiam wrote: Can I do this in COM No. :) If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile. This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke [My articles]

Continuation of above reply .... you can use overlapped-IO operation for communication with serial com port. Read code snippet for overlapped-IO is given below: DWORD dwRead; BOOL fWaitingOnRead = FALSE; OVERLAPPED osReader = {0}; // Create the overlapped event. Must be closed before exiting // to avoid a handle leak. osReader.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); if (osReader.hEvent == NULL) // Error creating overlapped event; abort. if (!fWaitingOnRead) { // Issue read operation. if (!ReadFile(hComm, lpBuf, READ_BUF_SIZE, &dwRead, &osReader)) { if (GetLastError() != ERROR_IO_PENDING) // read not delayed? // Error in communications; report it. else fWaitingOnRead = TRUE; } else { // read completed immediately HandleASuccessfulRead(lpBuf, dwRead); } } buntyrolln

Have a look here: http://msdn.microsoft.com/en-us/library/ms682623(VS.85).aspx[^]

kuttiam wrote: I need to initialize it in the constructor. But, the compiler is giving an error. You should initialize a reference variable in the constructor initialization list e.g. class MyClass { public: MyClass( int& RefVal ) : m_RefVal( RefVal ) // Ok { m_RefVal = RefVal;// Error, cannot do this here } private: int& m_RefVal; }; Since a reference variable is much like a constant var it must be initialized like a const var. i.e. initialize where it's declared and in classes we cannot initialize where it's declared hence initialization list is provided. Nibu thomas Microsoft MVP for VC++ Code must be written to be read, not by the compiler, but by another human being. Programming Blog: http://nibuthomas.wordpress.com modified on Wednesday, May 28, 2008 5:10 AM

kuttiam wrote: Can any one tell me how to post a message... Other than PostMessage()? "Love people and use things, not love things and use people." - Unknown "To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Just to add a little to Cedric's explanation: Visual Studio supports dynamic and static linking of MFC. With dynamic linking, your application is linked to an import library for MFC. The first time it calls an MFC function, the matching function in the import library sets things up so that this and future calls are to the proper function in the MFC DLL. Using static linking, your application calls functions directly in an MFC object library. The DLL is not required in this case. The advantage of dynamic linking is that your .EXE file is much smaller. The disadvantage is that you must make sure that the correct version of the MFC DLL is installed when you install your application. The advantage of static linking is that you don't have to worry about the installed version of MFC, since all of the required code is linked directly into your application. The disadvantage, obviously, is that your .EXE is much larger. Software Zen: delete this; Fold With Us![^]

Hi, Thanks for ur reply. I am trying to write a message box hook. In that i need to differentiate the message box from other windows and dialogs. I tried your suggestion but i could not achieve that :((. I appreciate your help.:)