On Sunday, 22 June 2025 at 00:44:42 UTC, Jonathan M Davis wrote:
>
> As for Darwin or whether we need `__APPLE__` (or whatever we call it) as a replacement, well, I'm not familiar enough with Apple's OSes to weigh in on that.
>
> - Jonathan M Davis

Maybe in that case we can fix all other versions as well..
And just some examples from other langs (from gpt)

```rust
use std::env;

fn main() {
    let os = if cfg!(target_os = "linux") {
        "linux"
    } else if cfg!(target_os = "macos") {
        "macos (Darwin)"
    } else if cfg!(target_os = "ios") {
        "ios (Darwin)"
    } else if cfg!(target_os = "windows") {
        "windows"
    } else {
        "unknown"
    };

    println!("Running on: {}", os);
}
```

Rust: all small letters - consistent

```swift
import Foundation

func getOSName() -> String {
    #if os(Linux)
    return "linux"
    #elseif os(macOS)
    return "macos (Darwin)"
    #elseif os(iOS)
    return "ios (Darwin)"
    #else
    return "unknown"
    #endif
}

print("Running on: \(getOSName())")
```

Swift: playing with all proper names (see Linux with capital)

```go
package main

import (
	"fmt"
	"runtime"
)

func main() {
	os := runtime.GOOS
	var osName string

	switch os {
	case "linux":
		osName = "linux"
       case "ios":
                osName = "darwin (iOS)"
	case "darwin":
		osName = "darwin (macOS)"
	default:
		osName = "unknown"
	}

	fmt.Printf("Running on: %s\n", osName)
}
```

Go: all small letters as well ("ios" support is a bit cumbersome though)

Consistency everywhere

On Sunday, 22 June 2025 at 03:40:44 UTC, Walter Bright wrote:
> Lots of good points, Jonathan.
>
> The current situation for C #defines for operating systems is an utter disaster. I can find zero official guidance from Apple on what to use.
>
> People have remarked that I was denigrating Linux by using lowercase "linux" as the version, but nothing of the sort was my intention. It was simply that "linux" was the most commonly used predefine in the Linux world.
>
> Maybe we should simply go with "Apple" as the umbrella for the various Apple operating systems, and be done with it. Maybe we can set a positive trend there! Wouldn't that be nice!

I’d propose 2 predefined versions;
'AppleOS` for all Darwin/mach derived apple OSes
'AppleMobileOS` for all apple OSes that use the mobile set of APIs (there’s different APIs between the mobile and desktop APIs)

This would make it easier to write software that targets both desktop and mobile Apple OSes.

On Sunday, 22 June 2025 at 14:25:37 UTC, Luna wrote:
> On Sunday, 22 June 2025 at 03:40:44 UTC, Walter Bright wrote:
>> [...]
>
> I’d propose 2 predefined versions;
> 'AppleOS` for all Darwin/mach derived apple OSes
> 'AppleMobileOS` for all apple OSes that use the mobile set of APIs (there’s different APIs between the mobile and desktop APIs)
>
> This would make it easier to write software that targets both desktop and mobile Apple OSes.

I like Luna's Solution. I already use `AppleOS` in my engine as well for handling that same issue.

And a PR:

https://github.com/dlang/dmd/pull/21471

Unfortunately, due to the needs of legacy compatibility, one winds up with multiple ways to express the same thing. Then we wind up with Apple's conundrum with Darwin, darwin, DARWIN, `__DARWIN__`, `__APPLE__`, `__MACH__`, etc.

> I'd never thought of that, I was just following normal C practice with the predefines.

Your idea is a good one, but I think it's a bit too late. I'm concerned about the disruption it could cause. People with a lot of code just don't care for even simple changes like search/replace. We've inflicted enough of that.