/SHARE
       /NOSHARE
    Specifies, for a disk volume, that the volume is shareable.
    If another user has already mounted the volume shareable, and
    you request it to be mounted with the /SHARE qualifier, any other
    qualifiers you enter are ignored.
    By default, a volume is not shareable, and the MOUNT command
    allocates the device on which it is mounted.
    If you previously allocated the device and specify the /SHARE
    qualifier, the MOUNT command deallocates the device so that other
    users can access it.
    The /SHARE qualifier is incompatible with the /GROUP and /SYSTEM
    qualifiers.
    Example
    The following command mounts the device labeled SLIP on DLA0,
    disables broadcasting of MOUNT messages, specifies that the
    volume is shareable, and assigns the logical name DISC:
    $ MOUNT/NOMESSAGE/SHARE DLA0: SLIP DISC