Standard output (stdout) is a fundamental concept in computing, referring to the default destination for output from command-line programs. In Unix-like systems, including macOS, stdout is typically the terminal window. Understanding how to manipulate and redirect standard output is crucial for efficient command-line usage, scripting, and system administration on macOS.

This article will guide you through the basics of using standard output in the macOS Terminal, including practical examples and commands tailored to the Apple environment.

Examples:

1. Basic Standard Output: The simplest way to see standard output is by running a command that produces output. For instance:

   echo "Hello, World!"

   This command will print "Hello, World!" to the terminal.

2. Redirecting Standard Output to a File: You can redirect the standard output of a command to a file using the > operator:

   ls -l > file_list.txt

   This command will save the output of ls -l to a file named file_list.txt.

3. Appending Standard Output to a File: If you want to append the output to an existing file, use the >> operator:

   echo "New line of text" >> file_list.txt

   This command will add "New line of text" to the end of file_list.txt.

4. Piping Standard Output: Piping allows you to pass the standard output of one command as input to another command. For example:

   ls -l | grep ".txt"

   This command will list all files and directories, but only display those that contain ".txt".

5. Using tee for Standard Output: The tee command reads from standard input and writes to standard output and files simultaneously:

   ls -l | tee file_list.txt

   This command will display the output of ls -l in the terminal and also write it to file_list.txt.