┌───────────────┬──────────┬──────────┬──────┬───────────┬─────┐ │ │ Absolute │ Relative │ File │ Directory │ UNC │ ├───────────────┼──────────┼──────────┼──────┼───────────┼─────┤ │ Symbolic link │ Yes │ Yes │ Yes │ Yes | Yes │ │ Junction │ Yes │ - │ - │ - | - │ └───────────────┴──────────┴──────────┴──────┴───────────┴─────┘
Let's assume we're creating a reparse point to create the redirect
C:\SomeDir => D:\SomeDir
Since this scenario only requires local, absolute paths, either a junction or symlink would work. In this situation, is there any advantage to using one or the other?
Assume Windows 7 for the OS, disregarding backward-compatibility. (Prior to Vista, symlinks are not supported natively, though there is a 3rd-party driver that provides symlink support on Windows XP.)
I have found another difference.
- Symbolic Link - Link's permissions only affect delete/rename operations on the link itself, read/write access (to the target) is governed by the target's permissions
- Junction - Junction's permissions affect enumeration, revoking permissions on the junction will deny file listing through that junction, even if the target folder has more permissive ACLs
The permissions make it interesting, as symlinks can allow legacy applications to access configuration files in UAC-restricted areas (such as %ProgramFiles%) without changing existing access permissions, by storing the files in a non-restricted location and creating symlinks in the restricted directory.