The company I work at creates custom function modules for use in older SAP systems. Performance is very important in these function modules. Recently I was working on several FMs that read attachments and do something with them.
Is there any centralized or more or less official way to know what in-built function modules are available in each release? Specifically when it comes to older function modules. Anything that is of helpful including any way to list the current system's function modules is appreciated.
Typically the process involves searching around on unofficial forums until I encounter a sufficient threshold of knowledge on in-built function modules I can use when I can construct a solution. I am very unhappy with this solution, this unofficial exploration by word of mouth really annoys me..
You can find existing function list at https://abapedia.org/ for newer versions. Also they have github repo, maybe there is some information about extraction tool.