A Parts-of-File File System

The Parts-of-file File System (PofFS) allows read-write accesses to different views of a given file or set of files in order to help the user separate and manipulate different concerns. The set of files is considered as a mount point from which views can be selected as read-write files via directories. Paths are formulas mentioning properties of a desired view. Each directory contain a file (the view) which contains the parts of the mounted files that satisfy the properties. This service is offered generically at the file system level, and a plug-in interface permits that file formats, or application-specific details are handled by user-defined operators. Special plug-ins called transducers can be defined for automatically attaching properties to parts of files. Performances are encouraging; files of 100 000 lines are handled efficiently.