File System Intermediate Directory Reparse Tag Handling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional file systems are unable to determine if a directory associated with a reparse tag contains the file to be opened or another directory, leading to incorrect implementation of reparse behavior, as they stop navigation upon encountering a reparse tag without looking beyond the node.

Innovation Solution

A file system or file system filter can decide whether to implement reparse behavior based on the presence of a next node in the intermediate directory by looking beyond the reparse tag, allowing for partial expansion of the directory and redirecting access as necessary.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the file system stops navigation upon encountering a reparse tag and automatically implements reparse behavior, then reparse behavior is implemented efficiently, but the file system cannot determine if the directory contains the file to be opened or another directory

Engineering Contradiction:
Improvereparse behavior implementation efficiencyVSAvoiddirectory content visibility
Core Design Contradiction:
ProductivityVSLoss of information

Solution Approach 1:

The patent applies local quality by making the reparse tag behavior context-dependent: when the reparse tag is on an intermediate directory, the file system continues navigation to check for next nodes, but when the reparse tag is on an end-point, it implements reparse behavior. This localized differentiation resolves the contradiction by allowing the system to maintain efficiency at end-points while gaining visibility into intermediate directory contents.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent introduces dynamic behavior where the file system's response to a reparse tag changes based on whether a next node exists in the intermediate directory. If a next node exists, navigation continues; if not, reparse behavior is implemented. This dynamic adaptation allows the system to balance between efficiency and information retrieval based on runtime conditions.

Inventive Principle:
Principle #15Dynamics

2Measurement precision

If the file system looks beyond the reparse tag into the intermediate directory to determine if the next node exists, then accurate file access determination is achieved, but navigation complexity increases

Engineering Contradiction:
Improvefile access determination accuracyVSAvoidnavigation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the navigation process into distinct phases: first checking for the existence of a next node in the intermediate directory, and then based on that result, either continuing navigation or implementing reparse behavior. This segmentation reduces complexity by breaking down the decision-making process into manageable, sequential steps rather than a single complex evaluation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediary check - determining whether a next node exists in the intermediate directory - that mediates between the reparse tag encounter and the final decision to implement reparse behavior or continue navigation. This intermediary step simplifies the overall logic by creating a clear conditional pathway.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Ease of operation

If conventional file systems consider a directory with reparse tag as an end-point, then navigation stops at that directory, but the system cannot handle cases where the directory contains additional nodes

Engineering Contradiction:
Improvenavigation simplicityVSAvoidintermediate directory handling capability
Core Design Contradiction:
Ease of operationVSAdaptability or versatility

Solution Approach 1:

The patent makes the end-point determination dynamic rather than static. Instead of automatically considering any directory with a reparse tag as an end-point, the system dynamically evaluates whether a next node exists. This dynamic approach maintains navigation simplicity for true end-points while adapting to handle intermediate directories that contain additional nodes, thereby resolving the contradiction between simplicity and versatility.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3371695B1Controlling reparse behavior associated with an intermediate directory
Publication Date: 2022.08.31 MICROSOFT TECHNOLOGY LICENSING LLC
  • EP3371695B1 patent drawingFigure 1
  • EP3371695B1 patent drawingFigure 2
  • EP3371695B1 patent drawingFigure 3

AI summary

The techniques and systems described herein determine whether or not to implement reparse behavior in association with a file or a directory access. A file system and/or a file system filter can receive, from a host system component, a request to open a file or a directory. While attempting to access the file or the directory, a reparse tag associated with an intermediate directory is encountered. The file system can then determine whether a next node, along an access path for the file or the directory to be opened, exists in the intermediate directory. That is, the file system can look beyond the reparse tag and into the intermediate directory to determine if the next node exists. Subsequently, the file system and/or the file system filter can decide whether to implement reparse behavior based on the reparse tag and whether the next node exists in the intermediate directory.