Fsutil is a file system utility that performs various command-line operations related to file allocation table (FAT) and NTFS file systems. It’s primarily used for managing tasks such as:
- Managing Reparse Points: These are special markers that allow files or directories to be associated with additional data or functionality.
- Managing Sparse Files: These files allocate disk space more efficiently by storing only non-zero data.
- Dismounting Volumes: Safely unmounting a volume from the file system.
If you use fsutil without any parameters, it displays a list of supported subcommands. Keep in mind that this command is quite powerful and should be used only by advanced users who have a thorough knowledge of Windows operating systems. You must also be logged on as an administrator or a member of the Administrators group to use fsutil.
Here are some of the specific subcommands and their purposes:
- 8dot3name: Queries or changes the settings for short name behavior on the system. For example, it can generate 8.3-character-length file names or remove short names for all files within a directory.
- devdrv: Manages dev drives, which are volumes tuned for developer scenarios and allow control over file system minifilters attached to the volume.
- dirty: Queries whether a volume’s dirty bit is set (which triggers an automatic error check on restart) or sets a volume’s dirty bit.
- file: Finds files by user name (if Disk Quotas are enabled), queries allocated ranges for a file, sets a file’s short name, valid data length, or zero data, and creates new files.
- fsinfo: Lists drives, queries drive type, volume information, NTFS-specific volume information, or file system statistics.
- hardlink: Lists hard links for a file or creates hard links (directory entries for a file). Hard links allow multiple directory entries to reference the same file.
- objectid: Manages object identifiers used by Windows to track objects like files and directories.
- quota: Manages disk quotas on NTFS volumes, providing precise control of network-based storage limits on a per-user basis.
Remember, fsutil is a powerful tool, so use it wisely!