xxx_Seek

The xxx_Seek function moves the data pointer in the device.

Syntax

DWORD xxx_Seek( DWORD hOpenContext long Amount DWORD Type );

Parameters

hOpenContext

Specifies a handle that identifies the open context of the device. The xxx_Open call returns this identifier.

Amount

Specifies the number of bytes to move the data pointer in the device. A positive value moves the data pointer towards the end of the file and a negative value moves it towards the beginning.

Type

Specifies the starting point for the data pointer:

FILE_BEGIN

Indicates the starting point is zero or the beginning of the file.

FILE_CURRENT

Indicates the current value of the file pointer is the starting point.

FILE_END

Indicates the current end-of-file position is the starting point.

Return Value

Returns –1 for an error, or the device's new data pointer for success.

Remarks

An application calls SetFilePointer to move the data pointer in the device. The operating system, in turn, invokes xxx_Seek. If your device is capable of being opened multiple times, xxx_Seek should only modify the data pointer for the instance specified by hOpenContext.