Wikipedia says it's based off RHEL and this[1] suggests it just vim.

1: https://dl-cdn.openeuler.openatom.cn/openEuler-25.03/source/...

Are they actually UNIX Conformant? That PDF just says they've entered a trademark license agreement. They're not listed in the conformance database.

https://www.opengroup.org/csq/search/t=XY1.html

> Are they actually UNIX Conformant? That PDF just says they've entered a trademark license agreement. They're not listed in the conformance database.

They were an official UNIX – https://www.opengroup.org/openbrand/register/brand3622.htm – but they aren't any more.

To be an official UNIX, you need to both pass the test suite and pay the trademark license fee. And the license fee needs to be renewed once every X years. And if you don't pay the renewal, you are no longer an official UNIX, even if you still pass all the tests.

This is why Solaris is no longer an official UNIX – someone at Oracle decided paying UNIX trademark license fees was a waste of money, so they stopped – and hence Solaris is no longer officially UNIX any more.

An I'm pretty sure the same thing happened with Huawei EulerOS. Probably someone at Huawei realised that zero customers cared whether EulerOS was officially "UNIX", and hence decided that paying the renewal was a waste of money. And they are probably right about that. 30 years ago, being officially "UNIX" or not could be a deal-breaker, nowadays I doubt a single customer cares.

FWIW, OS X uses vim so if any of the conformance tests check, it can be made to pass.

Solaris, AIX, and probably everyone else use the BSD/AT&T vi.

I used to work for Huawei. From what I remember, vi was just vim.

Somebody spent time and money to make vim posix-compliant: https://vimhelp.org/vi_diff.txt.html#posix