How to Switch Command Output to File on Windows

You may often run some commands in a Command Prompt or PowerShell in Windows, whether to perform administration, troubleshooting, or automation tasks. However, sometimes save the results into a text file, either for future reference, further analysis, or sharing with others.

How to do it? Do you have to manually copy and paste the command output into a text file? Of course not. There’s an easier and faster way to do that, and that’s to use the redirect operator.

The redirect operator is a special symbol that tells the shell (command interface) to change the direction of data flow from the standard (screen) to another place (file). Using redirect operators, you can send command output to text files easily and quickly.

In this article, you’ll learn how to use redirect operators to redirect command output to a file in Windows, using either Command Prompt or PowerShell. You will also learn some tips and tricks to make better use of this feature.

What is a redirect operator?

A redirect operator is a symbol used to change the direction of data flow from a standard (screen) to another place (file). There are several redirect operators you can use, depending on what you want to do with the command output.

Here is a list of the most commonly used redirect operators in Windows:

• >: This operator is used to redirect the command output to a new file. If the file already exists, then its contents will be overwritten by the command output.
• >>: This operator is used to redirect command output to an existing file. If the file does not already exist, a new file will be created. The output of the command will be appended to the end of the file without deleting the previous contents.
• <: This operator is used to take input from a file and pass it to the command. This is useful if you want to run a command with parameters stored in a text file.
• |: This operator is used to correlate the output of one command with the input of another command. This is referred to as pipelining, and it allows you to create a series of interdependent commands.

How to Use Redirection Operators in Command Prompt

Command Prompt is a Windows built-in command-line interface you can use to run various commands and programs. To use the redirect operator in Command Prompt, you just need to add it after the command you want to run, followed by the name of the destination file.

For example, if you want to run the “dir” command to view a list of files and folders in the current directory, and save the results to a file named “list.txt”, then you can type the following command:

dir > list.txt

This command will create a new file named “list.txt” in the current directory, and write the dir command output to it. If the file already exists, then its contents will be overwritten by the command output.

If you want to add the output of the “dir” command to an existing file, for example, “list.txt”, then you can use the “>>“ operator as follows:

dir >> list.txt

This command will add the output of the “dir” command to the end of “file list.txt”, without removing the previous contents. If the file does not already exist, a new file will be created.

You can also use the “<“ operator to pass input from a file to a command. For example, if you have a file named “commands.txt” that contains several commands that you want to execute sequentially, then you can type the following command:

cmd < commands.txt

This command will run a new shell (cmd) and provide input from the “commands.txt” file to that shell. Each line in the “commands.txt” file will be considered a command to run.

You can also use the “|” operator to correlate the output of one command with the input of another command. For example, if you want to run the “dir” command to view a list of files and folders in the current directory, and then run the “find” command to search for a specific file or folder, then you can type the following command:

dir | find “test”

This command will send the output of the “dir” command to the input of the find command, and look for the word “test” in that output. The results will be displayed on the screen.