[pjmlp]

There are naturally ABI breaks between major OS versions, outside of what POSIX requires.

[generichuman]

I will be even more impressed with linux syscall stability if your implication is that (some) people need to recompile their software for each major update on all other UNIXes.

[pjmlp]

Linux is only friendly for FOSS projects, it hardly has the same stability as commercial UNIX systems for closed source software.