HP OpenVMS Systems

Client-server programming? Terminal Emulators?

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The Question is:

 
We do have OpenVMS with all the program in Cobol and Rally. We do use terminal
 emulators to access de OpenVMS in PC with Microsoft Windows. These emulator do
 work fine. But now we are developing a program in Visual Basci and in one
 place we do have to mak
e an emulator to comunicate with the vms. I do have the code and connect the
 the vms via telnet and all works fine, but I do have some problems with the
 character set and keyboard codes. Is there any place where I could find some
 information about both pr
oblems.
 
Thanks
 
 

The Answer is :

 
  Install and use the available COM package for OpenVMS,
  and available packages such as BridgeWorks for OpenVMS.
  These allow you to jacket the applications, and to use
  protocols more directly compatible with those of the
  client environment.
 
  The OpenVMS Wizard would also encourage a review of CGI
  and of web-based (http) access, as this -- assuming
  compliance with available standards is maintained --
  avoids tying your applications to a particular client
  platform or client implementation.
 
  If you wish to learn about terminals and about serial
  communications, please see the information in the
  OpenVMS FAQ and in the OpenVMS I/O User's Reference
  Manual, as well as documentation for your terminal(s)
  or terminal emulators.  DECterm documentation is
  included in the DECwindows documentation set.  (The
  OpenVMS Wizard does not generally recommend using this
  approach -- sometimes called "screen scraping", but
  always a HACK.)
 
  If you must use this HACK, the OpenVMS Wizard would
  use the SYS$EXAMPLES:*LOGGER*.* example code or other
  similar approach, and particularly the OpenVMS
  pseudoterminal implementation, and create a layer
  that presents a cleanly-designed application-specific
  client-server network-based protocol out to the remote
  applications.  NOT A REMOTE SCREEN IMAGE.  This approach
  is clearly still a HACK, but it is one that avoids
  distributing the true core ugliness of the HACK out
  to multiple platforms.  This will then make it easier
  for future engineering efforts -- efforts that might
  seek to more cleanly connect to the application data
  -- simply because the cleanup of the HACK is limited
  to one host.
 

  

     

     
answer written or last revised on ( 16-NOV-2002 )
     
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