The inability to unmount a file system, often indicated by an error message stating the target device is busy, typically arises when processes are actively using files or directories within that file system. This can include open files, running programs, or active shell sessions within the mount point. For example, a user might encounter this issue when attempting to unmount a USB drive while files on the drive are open in a text editor or when a program is executing from that drive.
Resolving this issue is crucial for maintaining data integrity and system stability. Forcibly unmounting a busy file system can lead to data corruption or loss, and can disrupt running processes. Historically, the methods for identifying and terminating these processes have evolved alongside operating system development, from basic command-line tools to more sophisticated graphical utilities. Properly addressing this issue prevents data loss and ensures clean separation of the file system from the main system, allowing for safe removal of external devices or proper maintenance of internal file systems.
