DVM_GETERRORTEXT

The DVM_GETERRORTEXT message requests a user-mode video capture driver to return a text string associated with an error code.

Parameters

dwDriverID

Video channel identifier. One of VIDEO_EXTERNALIN, VIDEO_IN, VIDEO_OUT, VIDEO_EXTERNALOUT. (For details, see Opening Video Channels.) Can be NULL for this message.

hDriver

Driver handle.

uMsg

DVM_GETERRORTEXT

lParam1

Pointer to a VIDEO_GETERRORTEXT_PARMS structure.

lParam2

Not used.

Return Value

The driver should return DV_ERR_OK if the operation succeeds. Otherwise, it should return one of the DV_ERR error codes defined in msvideo.h.

Comments

A client sends the DVM_GETERRORTEXT message by calling the driver’s DriverProc entry point, passing the specified parameter values. Applications can send this message by calling the videoGetErrorText function, which is described in the Video for Windows Development Kit.

You can define customized error codes for a video capture driver. If you do, you need to also define a text string for each error code and place the strings in a resource (.rc) file. Clients use the DVM_GETERRORTEXT message to retrieve the text string for a specified custom error code.

Drivers should call the LoadString function, described in the Win32 SDK, to retrieve a string. This function truncates the string if the supplied buffer is too small.