Directory Program
cyls
volser
mode It is not advisable to define that a minidisk start at
real cylinder zero (unless the minidisk is to be used by OS ISA", in which case it must begin at real cylinder zero). If
you do assign a minidisk beginning at real cylinder zero, the
user who owns it must realize that the minidisk label is the
real label that both he and the V"/370 system use to identify
the disk. Also note that CP-owned volumes must not have
minidisks beginning at real cylinder zero.
is a 1-to 3-digit decimal number specifying the number of
cylinders. l1axi!!!'y,! lcylinder&
Disk DOS and VSAM CMS C"S_ 2314 200 203 200 2319 200 203 200 3330-1 or 2 404 246 404 3330-11 808 246 808 3340-35 346 348 348 3340-70 696 682 696
*3344 696 682 696 3350 555 115 555 The number of cylinders indicated for the 3344 is for
each of the four logical 3340-70 devices.
If the device is a 2314 or 2319 and it is to be formatted by
IBCDASDI, then the minimum minidisk size is two cylinders
because, for these devices, IBCDASDI reserves a cylinder at
the end of every minidisk for alternate tracks. For other
devices, the minimum size is one cylinder.
is the volume serial number of the DASD volume (1 to 6
alphameric characters).
is the primary access mode requested for the device
(read-only, write, or multiple-write), and the alternate
access (read-only or write) desired (if any). An optional 'V' character, when appended to the mode request, specifies
virtual RESERVE/RELEASE processing.
R specifies that read-only (RIO) access is requested. The
access is not given if any other user has the disk in
write status.
RR W specifies that read-only access is requested,
another user has the disk in write status.
specifies that write access is requested. The
not defined if any other user has the disk in
write status.
even if
disk is
read or WR specifies that write access is requested if no other
user has the disk in read or write status, but that an
alternate access of read-only is acceptable if others do
have a link to the disk. " specifies that multiple access is requested. This means
that a write link is to be given to the disk unless
another user already has write access to it, in which
case no link is to be given. 208 IB" V"/370 Planning and System Generation Guide

pr
pw
pm
Page of GC20-1801-10 As Updated March 3, 1980 by TNL GN25-0776 Directory Program
MR specifies that a write link is to be given to the disk
unless another user already has write access to it. In
this case, a read link is given to the user and the "DEV xxxx FORCED R/O" message is issued. MW specifies that a write link is to be given to the disk
in any case. V specifies that CP's virtual reserve/release support is
to be used in the I/O operations for the specified
device. The V is appended to the immediate right of the
primary access mode specification (or the alternate
access mode specification, if any). Thus, if the mode
specified for a minidisk is MWV, then the mini disk will
function with write linkage using CP's virtual
reserve/release functione
If a mode specification is omitted from the statement, it
defaults to W. is the password that allows sharing in read mode (a 1- to
8-character field).
is the password that allows sharing in write mode (a 1-to
8-character field).
is the password that allows sharing in multiple-write mode (a
1- to 8-character field).
1. A write password (pw) cannot be specified without a read password
(pr); a multiple-write password (pm) cannot be specified without 1:oth a read password (pr) and a write password (pw).
2. If a password of ALL is used for pr, pw, or pm,
the owner of the minidisk is allowed to link
without specifying a password.
a user other than
to this minidisk
3. When MSS support is used
t the volume serial number may specify an MSS 3330V volume. In this case, the volume serial number must be
six characters long.
4. If the MSS communicator is initialized when the virtual machine
logs on and the system volume having a volume label of 'volser' is
not mounted, then VM/370 will attempt to find an available SYSVIRT 3330V and mount 'volser' on that device.
5. If virtual Reserve/release processing is requested, minidisk users
with read or write access are prevented from accessing the minidisk
if the minidisk is reserved by another virtual machine. MDISK 230 3330 5 10 WORKOl W ALL WRITE is an MDISK statement for a minidisk with read/write access to 10 cylinders located on a real 3330 disk volume labeled WORK01, beginning at real cylinder 5. A user other than the owner of this
minidisk can link to it in read status without specifying a read
password, but must specify a password of 'WRITE' in order to gain
write access to it. Part 2. Defining Your VM/370 System 209 -------.,