GetTapeParameters info  Overview  Group

The GetTapeParameters function retrieves information that describes the tape or the tape drive.

DWORD GetTapeParameters(

HANDLE hDevice,	// handle of open device
DWORD dwOperation,	// type of information requested
LPDWORD lpdwSize,	// address of returned information
LPVOID lpTapeInformation	// tape media or drive information
);

Parameters

hDevice

Identifies the device about which information is sought. This handle is created by using the CreateFile function.

dwOperation

Specifies the type of information requested. This parameter must be one of the following values:

Value	Description
GET_TAPE_MEDIA_INFORMATION	Retrieves information about the tape in the tape device.
GET_TAPE_DRIVE_INFORMATION	Retrieves information about the tape device.

lpdwSize

Points to a variable that receives the size, in bytes, of the buffer specified by the lpTapeInformation parameter. If the buffer is too small, this parameter receives the required size.

lpTapeInformation

Points to a structure that contains the requested information. If the dwOperation parameter is GET_TAPE_MEDIA_INFORMATION, lpTapeInformation points to a TAPE_GET_MEDIA_PARAMETERS structure.

If dwOperation is GET_TAPE_DRIVE_INFORMATION, lpTapeInformation points to a TAPE_GET_DRIVE_PARAMETERS structure.

Return Values

If the function succeeds, the return value is NO_ERROR.

If the function fails, the return value is one of the following error codes:

Error code	Description
ERROR_BEGINNING_OF_MEDIA	An attempt to access data before the beginning-of-medium marker failed.
ERROR_BUS_RESET	A reset condition was detected on the bus.
ERROR_END_OF_MEDIA	The end-of-tape marker was reached during an operation.
ERROR_FILEMARK_DETECTED	A filemark was reached during an operation.
ERROR_SETMARK_DETECTED	A setmark was reached during an operation.
ERROR_NO_DATA_DETECTED	The end-of-data marker was reached during an operation.
ERROR_PARTITION_FAILURE	The tape could not be partitioned.
ERROR_INVALID_BLOCK_LENGTH	The block size is incorrect on a new tape in a multivolume partition.
ERROR_DEVICE_NOT_PARTITIONED	The partition information could not be found when a tape was being loaded.
ERROR_MEDIA_CHANGED	The tape that was in the drive has been replaced or removed.
ERROR_NO_MEDIA_IN_DRIVE	There is no media in the drive.
ERROR_NOT_SUPPORTED	The tape driver does not support a requested function.
ERROR_UNABLE_TO_LOCK_MEDIA	An attempt to lock the ejection mechanism failed.
ERROR_UNABLE_TO_UNLOAD_MEDIA	An attempt to unload the tape failed.
ERROR_WRITE_PROTECT	The media is write protected.

Remarks

The block size range values (maximum and minimum) returned by the GetTapeParameters function called with the dwOperation parameter set to the GET_TAPE_DRIVE_INFORMATION value will indicate system limits, not drive limits. However, it is the tape drive device and the media present in the drive that determine the true block size limits. Thus, an application may not be able to set all the block sizes mentioned in the range obtained by specifying GET_TAPE_DRIVE_INFORMATION in dwOperation.

See Also

CreateFile, SetTapeParameters, TAPE_GET_DRIVE_PARAMETERS, TAPE_GET_MEDIA_PARAMETERS