Each gateway is a pair of scripts. The first script is a Cshell script that sets the environment variables for the SQL session. The second script is a Perl script that interacts with the database.
Add Function:
OR_add sets environment variables and runs OR_add.pl.
Update Function:
OR_updt sets environment variables and runs OR_update.pl. OR_update.pl builds a form which points to OR_change. OR_change sets environment variables and runs OR_change.pl.
Search Function:
OR_srch sets environment variables and runs OR_search.pl.