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====== Brainteaser: More ======

Here's an interesting thing to think through:

Normally, the standard input (stdin) of a program is used for input from the terminal. For example, the ''nano'' editor uses stdin to get keystrokes from the user.

The output of any command or program that produces a lot of text can be piped into the ''more'' program so that is displayed one screen at a time to the user. For example, you can take the output of the ''ls'' command and direct it into ''more'' like this: 

<code>
ls | more</code>

When used in this way, the stdin of the ''more'' command is connected to the ''ls'' command. Therefore, it can't be used to get keystrokes from the user.

**How does ''more'' read the keyboard to determine when the user presses a key to see the next screen?**

(The same concept applies to both the Windows and Linux version of ''more'', as well as to the Linux ''less'' command).

Try to determine the solution, then [[More Solution|click here to check your answer]].