6. The Linux Filesystem

In This Chapter

The Hierarchical Filesystem 200 Directory Files and Ordinary Files 200 The Working Directory 204 Your Home Directory 204 Pathnames 205 Relative Pathnames 206 Working with Directories 207 Access Permissions 215 ACLs: Access Control Lists 221 Hard Links 228 Symbolic Links 230

A filesystem is a set of data structures (page 1144) that usually resides on part of a disk and that holds directories of files. Filesystems store user and system data that are the basis of users’ work on the system and the system’s existence. This chapter discusses the organization and terminology of the Linux filesystem, defines ordinary and directory files, and explains the rules for naming them. It also shows how to create and delete directories, move through the filesystem, and use absolute and relative pathnames to access files in various directories. It includes a discussion of important files and directories as well as file access permissions and Access Control Lists (ACLs), which allow you to share selected files with other users. It concludes with a discussion of hard and symbolic links, which can make a single file appear in more than one directory.