Page of GC20-1806-9 As Updated April 1, 1981 by TNL GN25-0834
ATTACH Use the ATTACH command to logically connect a real device to a virtual
machine for that virtual machine's exclusive use, or to logically
connect a DASD device for CP access and control. The operator usually
issues the ATTACH command to fulfill a user's request. The of the
ATTACH command is:
r----------------------------------------------------------------------------"
ATTach raddr [To] {USerid [As] vaddr [Rr/O]] [3330V] [VOLID VOlid]},' SYSTEM [As] volid I {
raddr... } I raddr-raddr (TO] userid [R[/O]] [3330V] I I raddr
raddr ••• raddr-raddr TO [ AS] vaddr
is the real address (cuu) of the device to be attached. On the command line, one real device address, multiple real
device addresses, or a range of real device addresses can be
specified. When the multiple or range form of raddr entry is used r the
real addresses are identical to the virtual addresses. When the range form of raddr is used (raddr-raddr), the values CUU-cuu must be entered with no imbedded blanks. The range
supplied must be contiguous addresses in ascending order with
the second address in the range being greater than the first.
userid is the user identification of the virtual machine that
is to receive the device(s). The user must be logged on to
receive the device(s). If the class B user is attaching the
device to his own virtual machine, the userid can be specified
as an asterisk (*). If the optional keyword "TO" is omitted,
the userid cannot be "TO" or "T". If a numeric userid of less
than four characters is specified with a range of addresses or
multiple device addresses, "TO" must be specified. When specifyinq a userid that could also be a valid hexadecimal
device address (for example, virtual machine id CE), the "TO" operand must be specified to distinguish it as a userid.
is the virtual address (cuu) to be assigned to the If
the optional keyword "AS" is omitted, vaddr cannot be "A" or "AS" • For USe of the vaddr operand, see Usage Note 6. R/O is optionally used for DASD devices that are attached to a
user. This allows the system operator to apply read-only
protection to a user's disk. The RIO operand may be truncated
to R. The R/O operand is ignored for all devices for which it
does not apply whenever more than one address is specified on
the command line.
Section 3. CP Commands 45

Page of GC20-1806-9 As Updated April 1, 1981 by TNL GN25-0834 [TO] SYSTEM specifies, along with vOlid, that the DASD made available to CP for accessing users'
paging and spooling functions.
device is to be
disks and/or for [AS] volid is the volume label of the volume on the raaar being attached.
This operand has the following meanings when used with the
various forms of the ATTACH command: • When used to attach an available raddr to a userid and the
raddr is a 3330V, the MSS volume with the label volid is
mounted on the raddr during the attach. • When used to attach an raddr to the system and the raddr is
not a 3330V, the volume label of the volume on raddr is
verified. • When used to attach an available raddr to the system and the raddr is a 3330V, the MSS volume with the label volid
is mounted on the raddr during the attach. • When used to attach an raddr to a userid and the raddr is
not a 3330V, the volid operand is 3330V specifies that the vaddr is to be treated as a 3330V. The VM/370 control program assumes the virtual machine contains MSS device support. Consequently, MSS cylinder fault support
is not invoked for the vaddr. VOLID volid VOLID is a required keyword and 'volid' is the volume label
for the 3330V being attached.
1. It is possible to attach a disk to "SYSTEM" and attach the same
disk to a user without first detaching the disk if the disk was not
accessed while it was attached to the system.
2. A 370x cannot be used by VM/370 as a 370x unless it has been loaded
by VM/370, DOS/VS or OS/VS with 270x EP program and VM/370 was
generated with it specified as a 2701, 2702, or 2703. The ATTACH
and DETACH commands reset the "loaded" status.
3. The ATTACH
unless all
command.
command should not be issued for a
emulator lines have been disabled 370x in
by the
PEP mode
DISABLE 4. If the device being attached is a 2305 then both the real device
address and the virtual device address must be specified as the
first exposure on the 2305 (that is, device address 0 or 8). When attaching or detaching a dedicated 2305 to a user, all eight
exposures are processed.
5. If the virtual machine to which the device is being attached has
the ECMODE option, any address up to X'FFF' is valid as 'vaddr';
otherwise, any address up to X'5FF' is valid.
6. The hexadecimal address of the virtual device (vaddr) that is
mapped to the real device must be selected with care so that
conflict and contention caused by control unit I/O interface
protocol is avoided. Omitting this parameter causes the assigning
of the raddr as a default. 46 t1 M .t':;li" , .. ;.I....J I v Operator's