# Tool Introduction

## Overview

US3FS mounts a US3 storage space (Bucket) to a local mount point on Linux/Windows. After mounting, you can access files in the bucket like local files.

## Version and Runtime Environment

### Software Versions

Current versions:

- Linux: v2.0.3
- Windows: v1.6.8

### Supported Environments

- Linux
  - CentOS 7.0 or later (check via `cat /etc/redhat-release`)
  - Ubuntu 16.04 or later (check via `cat /etc/issue`)
- Windows
  - WinFsp service enabled

## Key Features

- Supports most POSIX filesystem features: read, sequential write, permissions, UID/GID.
- Uses US3 multipart upload for large files.
- Supports ETag and MD5 validation to ensure data consistency.

## Limitations

- Does not support reading ARCHIVE storage class objects.
- Does not support random write / append write.
- `rename` is not atomic.
- Does not support hard/soft links.
- When multiple clients mount the same bucket, users must manage data consistency themselves.