Chapter 6. Redirecting I/O
Many Unix programs read input (such as a file) and write output in a standard way that lets them work with each other. In this chapter, we discuss some of these tools and learn how to connect programs and files in new and powerful ways.
This chapter generally doesn't apply to full-screen programs, such as the vi editor, that take control of your whole Terminal window. ( less and more do work together in this way, however.) It also doesn't apply to graphical programs, such as the Finder or Safari, that open their own windows on your screen.