Does Windows have Inode Numbers like Linux?

Question

Does Windows have Inode Numbers like Linux? How does Windows internally manage files?

Answer 1

The terminology used is a bit different from what you'd find in the Unix world, however in terms of having an integer that uniquely identifies a file, NTFS and some Windows API expose the concept of "file IDs" which is similar.

You can query the file ID of an open handle via GetFileInformationByHandle. See nFileIndexHigh, nFileIndexLow; this is the high and low parts respectively of the file ID which is 64 bits.

NtCreateFile can also open a file by its ID. See the FILE_OPEN_BY_FILE_ID flag. You need a volume handle to open by file ID.

Answer 2

Yes it does. Generally called fileID. Try this in a Win8 command shell:

fsutil file queryfileid  <filename>

Answer 3

Yes. NTFS uses a B-Tree indexing system. Every file in the MFT has a 64 bit File Index Number. This number, called the File ID, uniquely identifies the file ONLY WITHIN ITS VOLUME. I.e., two files on two separate volumes on the same PC may have the same File ID. See this MSDN article for more details.

https://msdn.microsoft.com/en-us/library/windows/desktop/aa363788(v=vs.85).aspx

regarding your second question, "how does windows internally manage files", see this technet article:

https://technet.microsoft.com/en-us/library/cc781134(v=ws.10).aspx

Answer 4

There are two things here. The term INode, and a file-system implementation that uses either INode terminology or something like INode in its place.

All Windows file-systems(FAT*,NTFS) I know of, use Inode-like structures in actual implementation.

To further simplify the answer

(Think of INode as a block of metadata about a file.)

INode as term : No windows file system dont have it.

INode as concept : Windows will have some other structures, similar in property and usage but used with different name