Is it legal to call functions from libSystem.Native?

[sakno]

.NET 6 provides awesome way to call some PAL functions via PInvoke even in case of single-file deployment. For instance, I have the following code:

[DllImport("libSystem.Native", EntryPoint = "SystemNative_GetPwUidR", SetLastError = false)]
internal static extern int GetPwUidR(uint uid, out Passwd pwd, ref byte buf, int bufLen); // buf must be pinned, I know

The immediate caller of this function is guarded by OperatingSystem.IsLinux() condition. According to #41299 and #44505, CLR interprets such an import as a statically linked function. So my questions are:

• Is this legal for use in libraries outside of .NET repo?
• Is this really compatible with any deployment mode, including AOT?

[stephentoub]

Is this legal for use in libraries outside of .NET repo?

libSystem.Native is implementation detail. It is not supported for use outside of the shared framework itself.

[sakno]

I understand that. Anyway, if I accept the risk of incompatible changes in the future, is it working properly with AOT?

[gfoidl]

You're on thin ice anyway, so why don't just try it?
And "properly" in the context of unsupported scenarios is the wrong term 😉.

[Xyncgas]

It depends on the states, also it might not work 😂