Linux, in the tradition of UNIX-like operating systems, implements file system permissions using a rather coarse scheme. While this is sufficient for a surprisingly large set of applications, it is too inflexible for many other scenarios. For that reason, all the major commercial UNIX operating systems have extended this simple scheme in one way or the other. This is an effort to implement POSIX-like Access Control Lists for Linux. Access Control Lists are built on top of Extended Attributes, which can also be used to associate other pieces of information with files such as Filesystem Capabilities, or user data like mime type and search keywords.
Linux NTFS provides Linux kernel drivers, a multiplatform NTFS library, and tools to create, resize, clone, rescue, query, label and fix NTFS volumes, and to undelete, resize, list, and query files for the filesystem used by Windows XP, 2003, 2000, NT4, and Vista. It also provides support for the Logical Disk Manager (LDM) that controls Windows' Dynamic Disks and is used to create software mirrors, stripes, and RAID.
Panasync Tools provides a set of commands that enables version tracking among plain file copies. Retaining the basic functionality of standard copy commands, one can always track if a file has seen more updates than another file, and determine redundant or equivalent file copies. The approach is totally decentralized and serverless, and the functionality is achieved by small command-line user level programs that manipulate (by duplicating, comparing, joining and moving) any given file. By copying files with these commands users can detect if those files forgotten on disks or dispersed on different file systems and computers hold obsolete versions, and can thus be deleted, or need to be merged when depicting parallel updates. The updates, themselves can be done by any application since the system keeps a digest of the files to detect changes.
FAM, the File Alteration Monitor, provides an API which applications can use to be notified when specific files or directories are changed. It comes in two parts: fam, the daemon which listens for requests and delivers notification, and libfam, a library which client applications can use to communicate with fam.