Unix® and Linux® System Administration Handbook, Fourth Edition

31. Serial Devices and Terminals

An operating system with over 40 years of history is sure to be dragging some cruft along with it. Some would put support for serial devices into this category, arguing that it’s a technology from a bygone era that is best forgotten. Compared to today’s multi-megabit serial interfaces such as USB, traditional serial ports may indeed seem too slow and twiddly to be useful.

In fact, an understanding of serial interfaces is an essential component of any system administrator’s tool box. For better or worse, the UNIX command-line interface is based on the ancient concept of a serial terminal and the associated commands ...