XXX_Seek (Device Manager) (Compact 2013)

3/26/2014

This function moves the data pointer in the device.

Syntax

DWORD XXX_Seek(
  DWORD hOpenContext,
  long Amount,
  WORD Type 
);

Parameters

• hOpenContext
  [in] Handle to the open context of the device. The XXX_Open (Device Manager) function creates and returns this identifier.

• Amount
  [in] Number of bytes to move the data pointer in the device. A positive value moves the data pointer toward the end of the file and a negative value moves it toward the beginning.

• Type
  [in] Starting point for the data pointer. The following table shows the available values for this parameter.

  Value	Description
  FILE_BEGIN	Indicates that the starting point is zero or the beginning of the file.
  FILE_CURRENT	Indicates that the current value of the file pointer is the starting point.
  FILE_END	Indicates that the current end-of-file position is the starting point.

Return Value

The new data pointer for the device indicates success. A value of -1 indicates failure.

Remarks

After an application calls the SetFilePointer function to move the data pointer in the device, the operating system invokes this function. If your device is capable of opening more than once, this function modifies only the data pointer for the instance specified by hOpenContext.

Device Manager uses the XXX prefix as a placeholder. When implementing the stream interface, replace XXX with a prefix appropriate for your implementation or use undecorated entry point names in conjunction with DEVFLAGS_NAKEDENTRIES. For more information about other valid Flags values, see ActivateDeviceEx.

Requirements

See Also

Reference

Stream Interface Driver Functions
ActivateDeviceEx
XXX_Open (Device Manager)

Other Resources

SetFilePointer