CHIO(1)                 NetBSD General Commands Manual                 CHIO(1)

     chio -- medium changer control utility

     chio [-f changer] command arg1 arg2 [arg3 [...]]

     chio 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.

     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''.

     chio 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-

     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-

     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

     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

     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.

     CHANGER  The default changer may be overridden by setting this environ-
              mental variable to the desired changer device.

     /dev/ch0 - default changer device

           chio -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.

     mt(1), mount(8)

     A chio utility appeared in NetBSD 1.3.

     The chio program and SCSI changer driver were originally written by Jason
     R. Thorpe for And: Communications.  Additional devel-
     opment was done by Jason R. Thorpe for the Numerical Aerospace Simulation
     Facility, NASA Ames Research Center.

NetBSD 8.1                      August 25, 2016                     NetBSD 8.1

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