To avoid the possibility
of another user mounting a particular device before you enter the
MOUNT command, you can optionally allocate the device before issuing
the MOUNT command. Use the DCL command ALLOCATE to provide your
process with exclusive access to a physical device until you either
deallocate the device or terminate your process. Optionally, you
can associate a logical name with the device. The format for the
ALLOCATE command is as follows: ALLOCATE device-name[:] logical-name[:]