If I had to do it, I would print something like {Page nn of {xx}” on each page. The “nn” would be the actual page number, but the “{xx}” would be some identifiable constant that is guaranteed not to be anywhere else in the output except where the page count is intended to be.

I would generate the output and close the file. Then I would either retrieve the count of pages from the spooled file attributes or I’d grab the value from wherever I stored it in the program.

Finally, I would use the Get Spooled File Data (QSPGETSP) API to get the spooled output into one or more user spaces, and use the appropriate User Space APIs to change each occurrence of “{xx}” to the actual page count, and the Put Spooled File Data (QSPPUTSP) API to re-spool the output. The temporary original spooled copy could be deleted once the new copy is re-spooled.

Tom