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

wParam = (WPARAM) 0; 
lParam = (LPARAM) (LPVOID) (fpProc); 



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.
**  Unicode:** Declared as Unicode and ANSI messages.

See Also

Video Capture, Video Capture Messages, capSetCallbackOnError