Granted Patent B1

US 7,953,879 · App. 11/344,513 · Granted May 31, 2011

Abstract

Claims (64)

1. A method comprising:

detecting a request to access a file, wherein the file comprises a plurality of data streams; and

selecting one of the data streams to be accessed, based on a symbolic name associated with the one of the data streams, wherein

the detecting and the selecting are performed by a computing device implementing a file system,

a non-symbolic name is associated with the one of the data streams, and

the selecting comprises:

accessing a pointer associated with the symbolic name,

detecting that the pointer identifies an other symbolic name instead of one of the plurality of data streams, and

accessing an other pointer associated with the other symbolic name in response to the detecting.

2. The method of claim 1 , wherein the request to access the file is a request to open the file.

3. The method of claim 1 , further comprising:

associating the symbolic name with the one of the data streams included in the file.

4. The method of claim 3 , wherein

the one of the data streams is a non-default data stream.

5. The method of claim 3 , wherein

the one of the data streams is a default data stream.

6. The method of claim 5 , further comprising:

creating the file, wherein the creating the file comprises the associating the symbolic name with the one of the data streams.

7. The method of claim 1 , wherein

the symbolic name comprises one of: a desktop shortcut icon and a name of a symbolic link.

8. The method of claim 1 , wherein the request to access the file specifies the symbolic name.

9. The method of claim 1 , wherein

each of the data streams stores a respective point-in-time copy of user data; and

the symbolic name is associated with a most-recently-created data stream of the data streams.

10. A system comprising:

computer readable storage means for storing metadata associated with a file, wherein the metadata comprises a symbolic name and a pointer associated with the symbolic name;

means for detecting a request to access a file, wherein the file comprises a plurality of data streams; and

means for selecting one of the data streams to be accessed, based on the symbolic name associated with the one of the data streams,

wherein

a non-symbolic name is associated with the one of the data streams, and

the means for selecting comprises:

means for accessing a pointer associated with the symbolic name,

means for detecting that the pointer identifies an other symbolic name instead of one of the plurality of data streams, and

means for accessing an other pointer associated with the other symbolic name in response to the detecting.

11. The system of claim 10 , wherein the request to access the file specifies the symbolic name.

12. A non-transitory computer readable medium comprising program instructions executable to:

maintain metadata, wherein the metadata identifies that a symbolic name is associated with one of a plurality of data streams, wherein the metadata includes the symbolic name and a pointer to the one of the plurality of data streams, and wherein a file comprises the plurality of data streams;

detect that the pointer identifies an other symbolic name—instead of one of the plurality of data streams;

access an other pointer associated with the other symbolic name in response to the detecting; and

update the metadata.

13. The non-transitory computer readable medium of claim 12 , wherein

the one of the data streams is a default data stream.

14. The non-transitory computer readable medium of claim 13 , further comprising program instructions executable to:

create the file, wherein creating the file comprises associating the symbolic name with the one of the data streams.

15. The non-transitory computer readable medium of claim 12 , further comprising program instructions executable to:

detect a request to access the file; and

select the one of the data streams to be accessed, based on the symbolic name.

16. The non-transitory computer readable medium of claim 12 , wherein the program instructions are executable to update the metadata by deleting the symbolic name.

17. The non-transitory computer readable medium of claim 12 , wherein the program instructions are executable to update the metadata in order to indicate that the symbolic name is associated with a second one of the plurality of data streams.

18. The non-transitory computer readable medium of claim 12 , wherein the program instructions are executable to create new metadata, wherein the new metadata identifies that a second symbolic name is associated with a second one of the plurality of data streams.

19. The non-transitory computer readable medium of claim 12 , wherein the program instructions are executable to create new metadata, wherein the new metadata identifies that a second symbolic name is associated with the one of the plurality of data streams.

20. A system comprising:

a storage device, wherein the storage device is configured to store a file comprising a plurality of data streams; and

a file system coupled to the storage device, wherein the file system comprises a symbolic data stream name module configured to:

detect a request to access the file,

select one of the data streams to be accessed, based on a symbolic name associated with the one of the data streams,

wherein

a non-symbolic name is associated with the one of the data streams,

detect that a pointer associated with the symbolic name identifies an other symbolic name instead of one of the plurality of data streams, and

access an other pointer associated with the other symbolic name in response to the detecting.

21. The system of claim 20 , wherein the symbolic data stream name module is further configured to:

associate the symbolic name with the one of the data streams included in the file by generating metadata comprising the symbolic name and pointer to the one of the data streams.

22. The system of claim 20 , wherein

the request to access the file specifies the symbolic name.

Assignments (11)