|
Managing Data Blocks by Polling
In addition to using a callback function, you can poll the dwFlags member of a WAVEHDR structure to determine when an audio device is finished with a data block.
Sometimes it is better to poll dwFlags than to wait for another mechanism to receive messages from the drivers. For
example, after you call the waveOutReset function to release pending data blocks, you can immediately poll to be sure
that the data blocks have been released before calling waveOutUnprepareHeader and freeing the memory for the data block.
You can use the WHDR_DONE flag to test the dwFlags member. As soon as the WHDR_DONE flag is set in the dwFlags member of the WAVEHDR structure, the driver is finished with the data block.
Related Links
Software for Delphi and C++ Builder developers
Software for Visual Studio .NET developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET
More Online Helps
Win32 Programmer's Reference (win32.hlp)
OLE Programmer's Reference (ole.hlp)
Microsoft Windows Pen API Programmer's Reference (penapi.hlp)
Microsoft Windows Sockets 2 Reference (sock2.hlp)
Microsoft Windows Telephony API (TAPI) Programmer's Reference (tapi.hlp)
Unix Manual Pages
|
