Chapter 12. Serial Lines and Devices

This chapter discusses how to work with serial lines on Unix systems. Traditionally, this meant configuring terminals and modems, but now the topic’s scope has grown to include related facilities as well, such as fax services and USB.

This chapter begins by considering traditional serial lines. First, we’ll look at the special files used for serial lines and other terminal sessions. Next, we will discuss how to set the characteristics of individual terminals and generic terminal types. We then go on to consider terminal line configuration issues, including how to add and troubleshoot new terminals and modems. We’ll conclude with a brief look at the HylaFAX fax service package and USB devices.


Celeste Stokely’s website, at, is an invaluable guide to all aspects of using serial ports on Unix systems.

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