DOCUMENT:Q186493 11-MAR-2001 [vbwin] TITLE :SAMPLE: LLStream.exe Plays Streaming Audio Files PRODUCT :Microsoft Visual Basic for Windows PROD/VER::5.0,6.0 OPER/SYS: KEYWORDS:kbfile kbsample kbsound kbVBp500 kbVBp600 kbGrpDSVB kbDSupport kbStreaming ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Visual Basic Learning Edition for Windows, version 5.0 - Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 - Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 ------------------------------------------------------------------------------- SUMMARY ======= LLStream.exe is a sample that contains a Visual Basic project that demonstrates how to play streaming audio files by calling several low-level functions in the Windows API. This sample helps you create a program that plays audio files continually without slowing down the operating system. MORE INFORMATION ================ The following files are available for download from the Microsoft Download Center: LLstream.exe (http://download.microsoft.com/download/vb50pro/samp34/1/WIN98/EN-US/LLstream.exe) The sample uses several low-level functions in the Windows API to work around the Multimedia Control Interface. You must be familiar with using Visual Basic to call the Windows API functions to understand how this sample works. When you run the self-extracting executable file, the following files are expanded into the Low-Level Streaming Audio Sample Project directory: - Form1.frm (3Kb) - the main form - Module1.bas (12Kb) - the module containing the function declarations - Project1.vbp (1Kb) - the main project file - Project1.vbw (1Kb) - the project workspace - Readme.txt - overview of the sample and download information The Multimedia Control Interface (MCI) is the one way to add multimedia capabilities to your program in Visual Basic. However, when you use the MCI to play audio files continuously, you can slow down or lock the operating system. This sample shows how to call the appropriate functions directly to work around the limitations of the MCI. Because the sample hooks into a Windows process, you should compile this sample and run the executable file rather than running the sample from the Visual Basic design environment. The sample uses the following functions in the Windows API: GlobalAlloc GlobalFree GlobalLock mmioAscend mmioClose mmioDescend mmioDescendParent mmioOpen mmioRead mmioReadString mmioSeek mmioStringToFOURCC PostWavMessage RtlMoveMemory waveOutClose waveOutGetDevCaps waveOutGetErrorText waveOutGetNumDevs waveOutGetPosition waveOutOpen waveOutPrepareHeader waveOutReset waveOutUnprepareHeader waveOutWrite Additional query words: ====================================================================== Keywords : kbfile kbsample kbsound kbVBp500 kbVBp600 kbGrpDSVB kbDSupport kbStreaming Technology : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600 Version : :5.0,6.0 Issue type : kbhowto ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.