CHIO(1) BSD General Commands Manual CHIO(1)NAMEchio — medium changer control utility
SYNOPSISchio [-f changer] command arg1 arg2 [arg3 [...]]
DESCRIPTIONchio is used to control the operation of medium changers, such as those
found in tape and optical disk jukeboxes.
The options are as follows:
-f changer
Use the device changer rather than the default device /dev/ch0.
The default changer may be overridden by setting the environment variable
CHANGER to the desired changer device.
A medium changer apparatus is made up of elements. There are four ele‐
ment types: picker (medium transport), slot (storage), portal
(import/export), and drive (data transfer). In this command description,
the shorthand ET will be used to represent an element type, and EU will
be used to represent an element unit. For example, to represent the
first robotic arm in the changer, the ET would be “picker” and the EU
would be “0”.
SUPPORTED COMMANDSchio move <from ET> <from EU> <to ET> <to EU> [inv]
Moves the media unit from <from ET/EU> to <to ET/EU>. If the optional
modifier inv is specified, the media unit will be inverted before inser‐
tion.
chio exchange <src ET> <src EU> <dst1 ET> <dst1 EU> [<dst2 ET> <dst2 ET>]
[inv1] [inv2]
Performs a media unit exchange operation. The media unit in <src ET/EU>
is moved to <dst1 ET/EU> and the media unit previously in <dst1 ET/EU> is
moved to <dst2 ET/EU>. In the case of a simple exchange, <dst2 ET/EU> is
omitted and the values <src ET/EU> are used in their place. The optional
modifiers inv1 and inv2 specify whether the media units are to be
inverted before insertion into <dst1 ET/EU> and <dst2 ET/EU> respec‐
tively.
Note that not all medium changers support the exchange operation; The
changer must have multiple free pickers or emulate multiple free pickers
with transient storage.
chio position <to ET> <to EU> [inv]
Position the picker in front of the element described by <to ET/EU>. If
the optional modifier inv is specified, the media unit will be inverted
before insertion.
Note that not all changers behave as expected when issued this command.
chio params
Report the number of slots, drives, pickers, and portals in the changer,
and which picker unit the changer is currently configured to use.
chio getpicker
Report which picker unit the changer is currently configured to use.
chio setpicker <unit>
Configure the changer to use picker <unit>.
chio status [<type> [unit [count]]] [voltags]
Report the status of all elements in the changer. If <type> is speci‐
fied, report the status of all elements of type <type>.
The status bits are defined as follows:
FULL Element contains a media unit.
IMPEXP Media was deposited into element by an outside human operator.
EXCEPT Element is in an abnormal state.
ACCESS Media in this element is accessible by a picker.
EXENAB Element supports passing media (exporting) to an outside human
operator.
INENAB Element supports receiving media (importing) from an outside
human operator.
If the element is a drive, the device name of the drive will be reported
if it is available.
If the [voltags] option is specified, primary and alternate volume tag
information will be reported, if available.
If the previous location of the media is available, it will also be
reported.
chio ielem
Perform an INITIALIZE ELEMENT STATUS operation on the changer.
chio cdlu <sub-command> <slot>
This command is provided for controlling CD-ROM changer mechanisms which
cannot use the standard changer control interface. ATAPI CD-ROM changers
fall into this category. There are 3 sub-commands:
load Loads the media from the specified slot into the CD-ROM drive.
unload Unloads the media from the CD-ROM drive and returns it to the
specified slot.
abort Aborts any pending load or unload operation.
FILES
/dev/ch0 - default changer device
EXAMPLESchio-f /dev/ch0 move slot 3 drive 0
Moves the media in slot 3 (fourth slot) to drive 0 (first drive).
chio setpicker 2
Configures the changer to use picker 2 (third picker) for operations.
chio-f /dev/cd0a cdlu load 1
Loads the media from slot (second slot) into the CD-ROM drive.
chio-f /dev/ch1 status
Returns status of all elements in the second changer.
SEE ALSOmt(1), mount(8)AUTHORS
The chio program and SCSI changer driver were originally written by Jason
R. Thorpe for And Communications, http://www.and.com/. Additional devel‐
opment was done by Jason R. Thorpe for the Numerical Aerospace Simulation
Facility, NASA Ames Research Center.
BSD September 8, 1999 BSD
