Unix Power Tools, 3rd Edition

Chapter 10. Linking, Renaming, and Copying Files

What’s So Complicated About Copying Files

At first glance, there doesn’t seem to be enough material to fill an entire chapter with information about linking, moving, and copying files. However, there are several things that make the topic more complex (and more interesting) than you might expect:

• In addition to moving and copying files, Unix systems also allow you to link them — to have two filenames, perhaps in different directories or even on different filesystems, that point to the same file. Section 10.3 explores the reasons why you want to do that; Section 10.4 discusses the difference between “hard” and “soft” links; Section 10.5 demonstrates how to create links; and other articles discuss various issues that can come up when using links.

• It’s nontrivial to rename a group of files all at once, but Unix provides many ways to circumvent the tedium of renaming files individually. In the chapter you’ll see many different ways to do this, exploring the variety in the Unix toolbox along the way.

• In a hierarchical filesystem, you’re sometimes faced with the problem of moving not only files but entire directory hierarchies from one place to another. Section 10.12 and Section 10.13 demonstrate two techniques you can use to perform this task.

— TOR

What’s Really in a Directory?

Before you can understand moving and copying files, you need to know a bit more about how files are represented in directories. What does it mean to say that a file ...