Q: We are running our AS/400 in a S/36 environment and have a lot of OCL and RPG II programs to convert.
Do you have any suggestions on software or books to help convert them to CL and RPG IV?
A: IBM used to provide a conversion toolset to move S/36 environment OCL and RPG II (aka RPG36) to S/38 CL and RPG III. I'm not sure whether that toolset is available today with the iSeries.
To convert from an RPG II source member to an RPG IV source member, you first have to move your RPG II source to RPG III. Basically, since the syntax is similar, you just need to start deleting things that are deprecated in RPG III. EXIT/RLABL comes to mind.
Once the source compiles as RPG III, you can convert it to RPG IV by using the CVTRPGSRC command included with your RPG compiler package.
Beyond that, you may want to check out one of the third party vendor tools that provide additional migration support.
As for OCL, there was a tool included with OS/400 that converted most of OCL to CL. I'm not certain if those tools still exist today. There are, however, vendors that provide similar tools. One that comes to mind is Linoma Software. You can also check the MC Press Vendor Directory for other vendors.
As for books on the subject, check out Paul Tuohy's Reengineering RPG Legacy Applications published by MC Press.