CHAPTER 18User Input Timeout

Sometimes you want a program that accepts user input to run automatically. If the user does not type anything within a specified amount of time, the program should continue running and use a default value for input.

A boot loader is a good example of this type of application. It would give the user a prompt where they will be able to choose the OS or kernel to be booted, but if the user lets the timeout expire, the boot loader uses a previously defined default operating system to boot the system.

An automated system-build script is another example. I wrote one to perform an automated system build while running from a bootable CD. This script would allow the user to choose how to build the system. If there were no ...

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