The capSetCallbackOnError macro sets an error callback function in the client application. AVICap calls this procedure when errors occur. You can use this macro or explicitly call the WM_CAP_SET_CALLBACK_ERROR message.

BOOL capSetCallbackOnError(



Handle to a capture window.


Pointer to the error callback function, of type capErrorCallback. Specify NULL for this parameter to disable a previously installed error callback function.

Return Values

Returns TRUE if successful or FALSE if streaming capture or a single-frame capture session is in progress.


Applications can optionally set an error callback function. If set, AVICap calls the error procedure in the following situations:

  • The disk is full.
  • A capture window cannot be connected with a capture driver.
  • A waveform-audio device cannot be opened.
  • The number of frames dropped during capture exceeds the specified percentage.
  • The frames cannot be captured due to vertical synchronization interrupt problems.


**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Vfw.h.

See Also

Creating an Error Callback Function, Video Capture, Video Capture Macros, capErrorCallback, WM_CAP_SET_CALLBACK_ERROR