chfn:tldr:9966b

The chfn command is a Linux/Unix command used to change the information associated with a user's account. Specifically, it is used to modify the User's GECOS (General Electric Comprehensive Operating System) information, which includes their full name and other details.

In this case, the command is chfn -f ${new_display_name} ${username}. Let's break it down:

• chfn: This is the command itself.
• -f: It is an option flag that indicates that we want to change the "Full Name" field of the user's account.
• ${new_display_name}: This is a variable placeholder for the new full name or display name you want to set for the user. You need to replace ${new_display_name} with the desired value.
• ${username}: This is another variable placeholder for the username of the user whose information you want to modify. You need to replace ${username} with the actual username you want to change.

So, when you execute this command by replacing the variables, it will modify the "Full Name" field or display name of the specified user's account.