CHAPTER 15Terminal Input and Output

Once upon a time, a terminal was a beige-colored box with a monochrome screen and a keyboard. In those days, computer rooms were populated with mainframes capable of supporting many simultaneous user sessions, and so, in order to allow simultaneous users, many terminals could be wired up to the computer, each with its own screen and keyboard. In order to save the computer from having to worry about every little detail of user input, such as scrolling the screen or dealing with the effect of a delete, terminals became progressively smarter, handling most of the minutiae of user input themselves and only sending the user's input to the computer when they hit the Return key. This meant the mainframe itself only ...

Get Pro Perl now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.