LeeTibbert

I moved the parts of this PR on which there seemed to be consensus to superseding PR #2671 so that those parts can be useful.

Some data, whilst I am waiting for a PR to pass.... I checked: `unit-tests/native/src/test/scala/scala/scalanative/unsafe/CVarArgListTest.scala` runs & passes on macOS, so there is hope ;-) (also gets run on Linux, Windows,...

Later: There is a `Variadic functions` section in the [Interop Guide] (https://scala-native.readthedocs.io/en/latest/user/interop.html) which may gives some clues as to usage. `toCVarArgList()` appears to not be in `.scala` code, so it...

@k3rnL Thank you for the progress note. Good to see a sandbox program working. Does that extend to & fix the problem you started out to solve? I find that...

@adamw Thank you for checking if this is current or fixed. I had thought that that the lines below fixed the problem ``` @name("curl_easy_setopt") def setopt(handle: Ptr[Curl], option: CInt, parameter:...

There is, however, one Scala Native MacOS related problem of which folks should be aware. I have a fix in the SN PR queue. SN 0.4.5 java.lang.Process fails on MacOS...

Since this is likely to be a general concern for a small community, would it be possible to post a URL for the fix. If agreeable, I would like to...

@ekrich @WojciechMazur Did this get put to rest by recently merged PR #3758?

I am still pecking away at removing deprecated items. I think I have 5+ files to go. Someday this Issue can Rest In Peace.

I believe this was fixed by @ekrich soon after the "extern trait" PR merged. Thank you, Eric.