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Disconnecting, Controlling Display Application?

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The Question is:

Is it possible to run up a terminal based application (that uses SMG),
 physically disconnect from it, leaving the 'terminal' still running and then
 reconnect at a later point in time, either from the same terminal or another?
 If so how.
For example, I wish to run up a terminal based application either via a
 DecWindows session or from a PC using either Exceed or Reflections TELNET. I
 then would like to facility to 'go home' leaving the application running. When
 at home I wish to reconnect
 to the session via either Exceed or Reflections TELNET and continue to use the
 application. Once satisfied, I wish to perform the reverse, disconnect from
 home and once back at work, reconnect to the application once more.
I already have the facility to log in from home. The application has no
 facility to spawn out from it.
Many thanks

The Answer is :

  Yes, this is possible using the virtual terminal mechanism that is
  present in OpenVMS, but most applications will eventually attempt one
  or more I/O operations to/from the display and will thus eventually
  hang pending the completion of the I/O.
  For details on virtual terminals, see the DCL commands CONNECT and
  DISCONNECT, as well as the associated timeout value established by
  the TTY_TIMEOUT system parameter setting.
  The pseudo-terminal mechanism is also available, if you wish to create
  an application that controls another program, via the target program's
  screen display.  The control program can run detached or otherwise, and
  can read and write input to the target program.  For details on the
  pseudo-terminal interface, please see the I/O User's Reference Manual.

answer written or last revised on ( 16-OCT-2001 )

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