Redirecting the Standard Input and Output Streams

Redirecting standard input and output of programs are commonly used especially on Unix-based operating system shells. (A shell is the program that interacts with the user in the terminal.) Some programs are designed to work well when piped to other programs.

For example, a file named deneme.d can be searched under a directory tree by piping find and grep as in the following line:

find | grep deneme.d

find prints the names of all of the files to its output. grep receives that output through its input and prints the lines that contain deneme.d to its own output.