C++ Primer Plus

Redirection

The standard input and output streams normally connect to the keyboard and the screen. But many operating systems, including Unix, Linux, and Windows, support redirection, a facility that lets you change the associations for the standard input and the standard output. Suppose, for example, that you have an executable Windows command prompt C++ program called counter.exe that counts the number of characters in its input and reports the result. (From most versions of Windows you can select Start, Programs and then click the Command Prompt icon to open a command-prompt window.) A sample run might look like this:

C>counterHelloand goodbye!Control-Z          << simulated end-of-fileInput contained 19 characters.C>

In this case, input came ...