I'm getting `platform.posix.TIOCGWINSZ` showing up...

# kotlin-native

[David Herman]

I'm getting platform.posix.TIOCGWINSZ showing up as undefined on macos. But as far as I can tell, that constant should be supported on the mac platform?

[David Herman]

What's weird is when I try to compile my code on a CI, it fails. But when I compile it on an old MBP I have lying around, compilation works. (But the IDE shows the symbol as unresolvable)

[David Herman]

Here's the code:

val numColumns = memScoped {
    val winsize = alloc<winsize>()
    ioctl(STDOUT_FILENO, TIOCGWINSZ, winsize.ptr)
    winsize.ws_col.toInt()
}

winsize and ioctl are found correctly.

[David Herman]

Note that this code lives in posixMain , not macosMain or anything more specific, in case that's what's causing the problem?

[David Herman]

(And in my project I target both macos x64 and macos arm64)

[David Herman]

I believe I've solved the issue. My CI is building at least.

I suspect what is happening here is that the TIOCGWINSZ constant provided by Linux is different from TIOCGWINSZ provided by Mac, so that the intersection stdlib provided at the posixMain parent layer excludes it.

I am using expect / actual machinery to work around the issue: https://github.com/varabyte/kotter/commit/02174741b1876d16a8640e4067b8cea42c141d62
(☝️ Basically, both macosMain and linuxMain provide exactly the same actual val TIOCGWINSZ: ULong = platform.posix.TIOCGWINSZ code, but K/N can resolve the constant correctly at those lower levels)