The Vary Device Off/On  command varies a device 'off' and  then 'on' to
reset  the  device.   If  a  Workstation device  is  named, the  Signon
display  is refreshed.   This  can be useful  if 'Signon  Text' is used
such as  with  the CHGSGNTXT  command.   An  option  exists to  name  a
subsystem to allocate the device to a 'HELD' status.

You must have *JOBCTL special authority to use VRYDEV.

VRYDEV  is intended  for a  simple reset  of the  device.   This allows
Signon  Text  (messages  on the  Signon  display) to  be  revised  on a
Workstation  display  even  though  the  Signon  prompt   is  currently
displayed.

Assume  you have  used  CHGSGNTXT  to change  the  text  on the  Signon
display.

A typical command to refresh the display would be:

             VRYDEV        DEV(xxx)

This  would vary the  device 'off' and  then 'on'.   The current status
of any  MSGID  keywords would  be  used to  refresh  the value  of  the
message text as seen on the display.

If  multiple  subsystems  have requested  the  device  and  the  signon
prompt still  exists, a single subsystem has the  device in HELD status
and  other subsystems are in a REQ (request)  or ASYNC status.  You can
refresh the  Signon  display for  a specific  subsystem  by naming  the
subsystem such as:

             VRYDEV        DEV(xxx) SBS(yyy)

This  will   place  the  Signon  display  associated   with  the  named
subsystem  on the  workstation and  the named  subsystem will  have the
device in a  HELD status.   The subsystem must  have been started  with
either the device or device type specified.

VRYDEV versus CHGSBSSGN
-----------------------

The CHGSBSSGN command  is part of the CHGSGNTXT tool.   CHGSBSSGN works
on  all  devices for  a specific  subsystem  and uses  VRYDEV  for each
device.

VRYDEV works on only a single device.

VRYDEV escape messages you can monitor for
------------------------------------------

      TAA9892    The subsystem does not have a request for the device
      TAA9893    Unable to satisfy the request
      TAA9897    No locks exist on the object

Escape messages from based on functions will be re-sent.

Command parameters                                    *CMD
------------------

   DEV           The device to be  varied 'off' and  then 'on'.   While
                 the  typical  use  is  for  workstation  devices,  any
                 device may be used.

   SBSD          The subsystem  to be used to place  the Signon display
                 on the workstation.  The default is *NONE.

                 If  *NONE  is used,  the  device is  varied  'off' and
                 then 'on'.

                 If  a  subsystem  is  named,  only  devices  that  are
                 currently   displaying   the    Signon   display   are
                 considered  (if the device is  currently signed on, no
                 change  occurs).    This  allows  the  Signon  display
                 associated  with the  named subsystem  to appear  even
                 though   a  different   subsystem  Signon   prompt  is
                 currently on the workstation.

                 The subsystem  must be  active and  must have  started
                 the device  or device type  (the status of  the device
                 must be HELD, REQ, or ASYNC).

                 If only  a single subsystem  has requested use  of the
                 device,  the function acts as  a refresh of the Signon
                 display.

                 If  multiple   subsystems  have   been  started   that
                 attempt  to   use  the  device,   the  last  subsystem
                 started  normally  has  the device  in  a  HELD status
                 awaiting  a  signon.     If  it   is  not  the   named
                 subsystem,  the  vary  'off' and  'on'  is  repeatedly
                 used until the named subsystem holds the device.

Restrictions
------------

You must have *JOBCTL special authority.

See the SBS parameter description.

Prerequisites
-------------

The following TAA Tools must be on your system:

     CHKSPCAUT       Check special authority
     CVTOBJLCK       Convert object lock
     SNDCOMPMSG      Send completion message
     SNDESCMSG       Send escape message

Implementation
--------------

None, the tool is ready to use.

Objects used by the tool
------------------------

   Object        Type    Attribute      Src member    Src file
   ------        ----    ---------      ----------    ----------

   VRYDEV        *CMD                   TAACFGF       QATTCMD
   TAACFGFC      *PGM       CLP         TAACFGFC      QATTCL
   TAACFGFC2     *PGM       CLP         TAACFGFC2     QATTCL