Use your favorite Internet search engine and you will find numerous examples of the syntax for using the QSNDDTAQ and QRCVDTAQ operating system APIs. The main point here is that you should use them in your physical file trigger programs. By limiting the logic in your trigger programs to basically just one call to an operating system API, you will be adding minimal performance impact to the jobs that update these Production database files.

You will have a "background" process that will CALL QRCVDTAQ and perform your custom logic. This batch process will be able to open the files once at IPL time. Programs will be able to stay in memory inside of this one batch job versus hundreds of jobs calling QSNDDTAQ.