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To put an hand to the cowboy programmers that were linking to system libraries not part of that list, starting with Android 7, they will be terminated if they try to do so.

https://developer.android.com/about/versions/nougat/android-...

The only form of binaries allowed on a standard Android device are shared objects.

The Native Activity is actually just the native method calls of https://developer.android.com/reference/android/app/NativeAc... that loads a shared object with a predefined name.

None of the stable NDK APIs are GNU/Linux specific and the POSIX layer isn't fully compliant with the standard, many APIs like e.g. SYS V IPC are missing.

http://www.cs.columbia.edu/~vatlidak/resources/POSIXmagazine...

https://roxanageambasu.github.io/publications/eurosys2016pos...

Rooted devices don't count, as that is not what people get on the store when they buy an Android device.

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billsix | karma 574 | avg karma 2.29 · | 2013-02-08 09:06:53

Android NDK. http://developer.android.com/tools/sdk/ndk/index.html

abdulla | karma 147 | avg karma 2.72 · | 2021-08-31 21:45:50

Android began restricting what APIs you could use in your app with Android 9: https://developer.android.com/guide/app-compatibility/restri...

Similarly, what is accessible from the NDK is limited: https://developer.android.com/ndk/guides/stable_apis

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pjmlp | karma 109153 | avg karma 1.76 · | 2019-06-29 08:09:38+00:00

iOS doesn't use Linux and on Android userspace doesn't actually see it.

https://developer.android.com/ndk/guides/stable_apis

So it is meaningless.

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harph | karma 74 | avg karma 2.24 · | 2011-02-10 14:26:38+00:00

NDK http://developer.android.com/sdk/ndk/index.html

I'm playing with it at the moment. It might seem a bit frustrating first, with all those JNI naming conventions and getting it to integrate with Eclipse, but hopefully it's performance will make up for it.

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pjmlp | karma 109153 | avg karma 1.76 · | 2016-11-14 20:17:41+00:00

Yes,

http://arstechnica.com/security/2016/09/linux-kernel-securit...

This is probably the only reason I can somehow understand Google's draconian approach to the NDK APIs, versus what iOS and UWP allow for.

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pjmlp | karma 109153 | avg karma 1.76 · | 2019-11-28 19:57:02

So how does it work around the missing APIs not described here?

https://developer.android.com/ndk/guides/stable_apis

Given the changes started with Android 7 to block access to everything else?

In fact, https://wiki.termux.com/wiki/Differences_from_Linux

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pjmlp | karma 109153 | avg karma 1.76 · | 2021-04-28 06:04:29+00:00

Where is POSIX listed here?

https://developer.android.com/ndk/guides/stable_apis

> Starting in Android 7.0, the system prevents apps from dynamically linking against non-NDK libraries, which may cause your app to crash. This change in behavior aims to create a consistent app experience across platform updates and different devices. Even though your code might not be linking against private libraries, it's possible that a third-party static library in your app could be doing so. Therefore, all developers should check to make sure that their apps do not crash on devices running Android 7.0. If your app uses native code, you should only be using public NDK APIs.

Taken from https://developer.android.com/about/versions/nougat/android-...

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