Overview
Duplicate File Detective provides robust duplicate file management capabilities, including:
- Support for finding duplicate files using a wide array of file comparison options
- Integrated SmartMark technology to assist in selecting duplicates for further processing
- Built-in support for moving, archiving, or removing duplicate files
In this article, we're going to focus on the last of the capabilities mentioned above -- the processing of duplicate files. Specifically, we'll be taking a closer look at the duplicate file linking capabilities provided by the product.
Scenario
Duplicate file linking is designed and engineered to address a specific problem - when duplicate files are removed from shared storage areas, users may be left unaware of the location of the original file that was retained. So the goal is to consolidate duplicate files without adversely affecting the workflow of your users.
Duplicate File Detective offers a solution -- when removing duplicate files, you can choose to create links back to the original file that you chose to retain. For example, if you have a group of three duplicate files, you can remove two of them and leave links pointing back to the one that was not removed.
Link Types
Duplicate File Detective offers three distinct duplicate file linking options, each with their own unique advantages and considerations.
- Shell shortcuts
- Hard links
- Symbolic links
In the sections that follow, this paper will elaborate on each of these linking methods, with the goal of helping you choose the best fit for your requirements.
Shell Shortcut Links
A Windows shell shortcut is simply a file, usually with a .lnk file extension, that contains pointer information to another file (the shortcut target).
A key point to remember about shell shortcuts is that they are really only recognized (and processed) by the Windows shell. For example, if a user is browsing files within Windows Explorer and attempts to open a file that has been linked via shell shortcut, the Windows shell will open the shortcut target instead. However, third-party programs may very well not follow shell shortcut links. If you're running a program that requires a data file to be present in a prescribed file system location, that program is unlikely to function correctly if you replace said data file with a shell shortcut link.
Another consideration is that removal (or relocation) of a file will usually break any shell shortcuts that point to it, effectively "orphaning" them. However, removing a shortcut will not affect the original file.
A big advantage of shell shortcuts is that they are supported on all versions of Windows and any file system type (NTFS, FAT32, etc.).
Hard Links
When a hard link is created, a new name is added for an existing entry in the local Master File Table (MFT). You can think hard links as being like "pointers" to the same physical file on a volume.
Hard links have the benefit of being highly transparent -- they behave identically to the original file. When a user or program opens a file identified by a hard link, they are opening the target file directly. No support is required by the Windows shell, for example, to interpret the linkage.
If a file is moved, any hard links to it will continue to function. If a file with multiple hard links is deleted, the file will persist until all other hard links are removed.
One caveat regarding hard links is that they must reside on the same volume as the original file. This means you cannot create hard links across drives, nor can you create hard links to a file on a network share. They also require NTFS, though they are supported by all versions of Windows.
Symbolic Links
Symbolic links are conceptually similar to shell shortcuts (described above), but are stored directly in the file system rather than being represented as a distinct file.
Importantly, support for symbolic links was introduced with Windows Vista / Server 2008, so older Windows operating systems will not recognize them.
Unlike hard links, symbolic links can span volumes and can even target files on a network share.
If a symbolic link is deleted, the original file will be unaffected. If the target file is moved or deleted, any symbolic links to it will become invalid.
Creating Duplicate File Links
Duplicate File Detective supports the creation of links via its powerful Duplicate File Manager tool. To use it, first search for duplicate files and mark the duplicate files in each group that you wish to process (move, archive, or delete).
Importantly, Duplicate File Detective can only create duplicate links in cases where only one member of a duplicate group is left unmarked. In other words, if a duplicate group contains four duplicate file entries, three of them must be marked for processing while the fourth is left unmarked.
After marking the duplicates files you wish to process, click the Move, Delete, or Zip button in the main window ribbon bar to launch the Duplicate File Manager. Select the duplicate file linkage option that is the most appropriate for your requirements.
Clicking the Go button will cause the Duplicate File Manager to process duplicate files according to the options you've chosen. When duplicate file linking is enabled, it will replace moved or deleted duplicates with a link to their unmarked sibling.
Conclusion
Duplicate file linking is a powerful tool that can help ease user transition during duplicate file consolidation efforts. However, it's important to understand the behaviors and requirements of each available linking option prior to using the feature.