mountpoint:tldr:38fa6

The mountpoint --fs-devno ${path-to-directory} command is used to determine whether a specific directory is a mountpoint and to display the device number of the file system that is mounted on it.

Here is a breakdown of each part of the command:

• mountpoint is the command that checks whether a directory is a mountpoint.
• --fs-devno is an option used with the mountpoint command to display the file system's device number.
• ${path-to-directory} is the path to the directory that you want to check. You should replace this with the actual path to the directory in question.

When you run this command, it will check if the specified directory is a mountpoint. If it is, it will display the device number of the file system that is mounted on that directory. The device number is a unique identifier assigned to the underlying storage device where the file system resides.