Hi, I got to write a wrapper in C to make use of winmm.dll. There is another application, which will use C wrapper to call winmm API's. Here is the C# code, can some body help me in converting to C code, I got to have this as dll. so I'm using vc++.net system32 app. ----------------------------------------------------------------------------------------------------------------------------------------------------- Code: [DllImport("winmm.dll")] private static extern long mciSendString( string strCommand, StringBuilder strReturn, int iReturnLength, IntPtr oCallback); public void OpenMediaFile(string strFileName) { PlayCommand = "Open \"" + strFileName + "\" alias MediaFile"; mciSendString(PlayCommand, null, 0, IntPtr.Zero); isOpen = true; } public void PlayMediaFile(bool loop) { if (isOpen) { PlayCommand = "Play MediaFile"; if (loop) PlayCommand += " REPEAT"; mciSendString(PlayCommand, null, 0, IntPtr.Zero); } } this is the code I have written, but incomplete --------------------------------------------------------------------------------------------------------- Code: long __declspec(dllimport) __stdcall mciSendStringA(char*, char *, int ,int *); int PlayMediaFile() { int out = 0; mciSendStringA("Play MediaFile", "", 0, &out); return 0; } I appreciate if someone help me here. thanks,