IOCTL_VVCR_SET_MECHANISM_STATE (Windows CE 5.0)
This IOCTL permits the caller to notify the virtual VCR driver of the current state of the tape mechanism.
Parameters
- hDevice
[in] Handle to the target object. To obtain a device handle, call the CreateFile function with a name dynamically obtained from the SetupDiEnumDeviceInterfaces function. - dwIoControlCode
[in] Set to IOCTL_VVCR_SET_MECHANISM_STATE. This value identifies the target operation and the type of device on which to perform the operation. - lpInBuffer
[in] Must be completed with a properly initialized VVCR_SetMechanismState_Request structure. The vsms_State member must be pre-initialized. - BufferSize
[in] Set to sizeof(VVCR_SetMechanismState_Request). - lpOutBuffer
[in] Unused. Should be set to NULL. - nOutBufferSize
[in] Unused. Should be set to 0. - lpBytesReturned
[out] Pointer to a DWORD that receives the actual count of bytes returned by the function in the output buffer. - lpOverlapped
[out] If not used, set to NULL. Otherwise, this should point to a completely filled out OVERLAPPED structure that contains a valid event. The event will be signaled when the I/O operation is complete.
Return Values
If the operation succeeds, the DeviceIoControl function returns a non-zero value. If the operation fails, DeviceIoControl returns zero. To obtain extended error information, call the GetLastError function.
Remarks
The virtual VCR driver keeps a cache of the last known state of the tape. This cache is update by the application by IOCTL_VVCR_SET_MECHANISM_STATE. When remote devices request the current state, the result is read from the cache of the virtual VCR driver. The application should issue this command when it internally changes state, such as from Stopped mode to Playing mode.
Requirements
OS Versions: Windows CE .NET 4.0 and later.
Header: Avc_vvcr.h.
See Also
CreateFile | DeviceIoControl | IOCTL_VVCR_SET_MECHANISM_POSITION | VVCR_SetMechanismState_Request
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