So far as WINE is concerned: At the end of the day, x86 is x86. Different operating systems use different loaders/dynamic linkers, different filesystem layouts

So far as WINE is concerned: At the end of the day, x86 is x86. Different operating systems use different loaders/dynamic linkers, different filesystem layouts, different APIs, but still the same machine code and still the same calling conventions. WINE, in a nutshell, merely presents the Windows environment (by wrapping Linux calls in Windows calls) to an executable that is running otherwise natively, there isn't a virtual machine or an emulator involved. There is no sandbox or security (as that is a non-goal). The problem is that various DRM and anti-cheat products use undocumented Windows syscalls to do their job, and syscalls are something that you can't just wrap with a function. This extension will allow WINE to ask Linux to send it unhandled syscalls (via SIGSYS), so that it can emulate them (making it a misnomer for the first time).