Abstract

A file sharing system, comprising a file access processor and a plurality of application support processors; and the file access processor, in turn, includes a central data access system and a storage system is provided to form directories from data in the database, and to change data in that database. Each support processor includes a local cache to acquire and hold directories formed by the data access system; and for each directory acquired by at least one support processor, the data access system further includes a directory gate and a multitude of directory change blocks holding information describing changes in the database that affect the directory. The directory change blocks established for a given directory are arranged in a first chain anchored to the directory gate established for the directory. For each support processor that has acquired at least one directory, the data access system further includes a directory acquired block for each directory acquired by the support processor. Preferably, the directory acquired blocks established for a given directory are arranged in a second chain also anchored to the directory gate established for the given directory.