mountpoint --version (return code: 0)
mountpoint from util-linux 2.27.1
mountpoint --help (return code: 0)
Usage:
mountpoint [-qd] /path/to/directory
mountpoint -x /dev/device
Check whether a directory or file is a mountpoint.
Options:
-q, --quiet quiet mode - don't print anything
-d, --fs-devno print maj:min device number of the filesystem
-x, --devno print maj:min device number of the block device
-h, --help display this help and exit
-V, --version output version information and exit
For more details see mountpoint(1).