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2.4.39 FilePositionInformation

This information class is used to query or set the position of the file pointer within a file.<141>

A FILE_POSITION_INFORMATION data element, defined as follows, is returned by the server or provided by the client.


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CurrentByteOffset

...

CurrentByteOffset (8 bytes): A 64-bit signed integer that MUST contain the offset, in bytes, of the file pointer from the beginning of the file. A unique offset value is maintained for each open of a file.  When setting the position, only values greater than or equal to zero are valid. If the given file was opened using the FILE_NO_INTERMEDIATE_BUFFERING flag, the offset that is being set SHOULD be aligned to a sector boundary. This value SHOULD<142> be updated by read and write operations if the given file was opened using the FILE_SYNCHRONOUS_IO_ALERT or FILE_SYNCHRONOUS_IO_NONALERT flags.

This operation returns a status code as specified in section 2.2. Upon success, the status code returned by the function that processes this file information class is STATUS_SUCCESS. The most common error codes are listed in the following table.

Error code

Meaning

STATUS_INFO_LENGTH_MISMATCH

0xC0000004

The specified information record length does not match the length that is required for the specified information class.

STATUS_INVALID_PARAMETER

0xC000000D

Returned when setting the offset if the CurrentByteOffset is negative or the file was opened using the FILE_NO_INTERMEDIATE_BUFFERING flag and CurrentByteOffset is not aligned to a sector boundary.