CHEOPS interface

If FATMEN has been installed with the CHEOPS option, users may request that files are copied between sites via the CHEOPS system. Requests will only be accepted at sites which also have the correct server configuration.

On VM/CMS systems, this requires a special service machine with username FMCHEOPS. This service machine receives copy requests from users on the local VM/CMS system and forwards them to the local CHEOPS server.

On Unix and VAX/VMS systems, an environmental variable/symbol FMCHEOPS must be defined. This points to a directory into which the copy requests will be automatically written by the FATMEN software.

The following steps are involved:

1. When a copy request is made, e.g. using the shell command COPY with the TRANSPORT=CHEOPS parameter or the FMCOPY subroutine with the K option, the FATMEN catalogue is updated with an entry corresponding to the destination file. The comment field contains the text

   Copy request queue to CHEOPS on YYMMDD at HHMM
   

2. Once the request has been processed by the CHEOPS server, the comment is changed to

   copy successfully queued to CHEOPS.
   

3. If there are errors processing the request, the comment becomes

   ERROR: <cheops error message>
   

4. Finally, once the transfer has been performed, the original comment as specified by the user is restored.
5. If the actual transfer failed, the reason for the failure is instead written into the comment string of the corresponding FATMEN entry.

• Building the FATMEN/CHEOPS interface on a Unix system
• Building the FMCHEOPS server on a VM/CMS system