On Windows, the stability guarantees are opposite to that of Linux. The kernel ABI is not guaranteed to be stable, whereas the Win32 ABI is.

And frankly, the Windows way is better. On Linux, the 'ABI' for nearly all user-mode programs is not the kernel's ABI but rather glibc's (plus the variety of third-party libraries, because Win32 has a massive surface area and is an all-in-one API). Now, glibc's ABI constantly changes, so linking against a newer glibc (almost certainly the 'host' glibc, because it is almost impossible to supply a different 'target' glibc without Docker) will result in a program that doesn't run on older glibc. So much for Torvalds' 'don't break userspace'.

Not so for a program compiled for 'newer' Win32; all that matters are API compatibilities. If one only uses old-hat interfaces that are documented to be present on Windows 2000, one can write and compile one's code on Windows 11, and the executable will run on the former with no issues. And vice versa, actually.

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samus an hour ago | parent | next [-]

The Win32 ABI is also just a wrapper on the native API, which is only stable in practice, but not officially according to any Microsoft documentation.

Glibc is userspace seen from the perspective of the Linux kernel.

	▲	delta_p_delta_x 21 minutes ago \| parent [-]
		It doesn't really matter if it's 'just a wrapper', because said wrapper provides an ABI. Even if the underlying Native API changes, the interface the wrapper presents to other compiled binaries won't. The latter will contain caller/callee register setup, type layouts, function arguments and more for that wrapper. Cygwin is also 'just a wrapper' for the Native API and Win32, and look how drastically it changes the ABI of applications.

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monocasa 2 hours ago | parent | prev [-]

A lot of the native API is considered stable these days. The actual signals aren't, but the wrappers in ntdll are.