The function checks if the input directory is a subdirectory of a mountpoint of a certain protocol. At the moment, it works only on unix operating systems.

mountpoint(path, protocol = NA)

## Arguments

path The path to be checked (optional) Vector of protocol types. If NA (default), all the protocols are considered.

## Value

The path of the parent mountpoint for mounted directories; if the input directory is not mounted, NULL is returned. NULL is returned also if the operating system is not unix (together with a warning message). An attribute "protocol" contains the protocol of the mountpoint.