Operating Systems: Concurrent and Distributed Software Design

24.5. File system implementation

In Section 24.4 we described the interface that an application uses when accessing the file system and the way in which directory names are presented to users. In this section we introduce the primary data structures that are used to implement a basic UNIX file system and show how these might be held on a disk.

24.5.1. Inodes

Central to each file system is a metadata table held on disk and cached in main memory in which each file occurring there has an entry (irrespective of whether it is a normal file, a directory file or a special file). These entries are called index nodes or inodes and contain information on the corresponding file. By convention, the inode of the root of a file system is the first entry in ...