This library provides functionality missing from .NET Core via system calls, that are called from from the CorePsPlatform.cs file of PowerShell. The method to do this is a Platform Invoke, which is C#'s Foreign Function Interface to C code (and C++ by way of extern C).

CMake is used to build the project, which results in a libpsl-native.so library on Linux, and libpsl-native.dylib on OS X.

cmake -DCMAKE_BUILD_TYPE=Debug .
make -j

The Google Test framework is used for unit tests.

Use either make test or ctest --verbose for more output.

Marshalling data from native to managed code is much easier on Linux than it is on Windows. For instance, to return a string, you simply return a copy of it on the heap. Since only one memory allocator is used on Linux, the .NET runtime has no problem later freeing the buffer. Additionally, .NET presumes that the codepage "Ansi" on Linux is always UTF-8. So just marshal the string as UnmanagedType.LPStr.

[DllImport("libpsl-native", CharSet = CharSet.Ansi)]
[return: MarshalAs(UnmanagedType.LPStr)]
internal static extern string GetSomeString();

char *GetSomeString()
{
    return strdup("some string");
}

The CoreFX team has an excellent guide for UNIX Interop.