What is an application binary interface (ABI)?

Question

I never clearly understood what an ABI is. Please don\'t point me to a Wikipedia article. If I could understand it, I wouldn\'t be here posting such a lengthy post.

Answer 1

The ABI needs to be consistent between caller and callee to be certain that the call succeeds. Stack use, register use, end-of-routine stack pop. All these are the most important parts of the ABI.