System.DllNotFoundException: libpcsclite.so.1 assembly:<unknown assembly> type:<unknown type> member:(null)

Question

Researched this issue many times but didn't found solution of it. Working with xamarin forms version 5.0.0.2012, on win 10 os (saw many solutions for mac or linux but didn't found any for windows), using PCSC library version 5.0.0. Trying to invoke context.Establish method while debugging on Android 8.0:

    public SimpleReader(ISCardContext context, bool releaseContextOnDispose = false)
    {
        if (context == null)
        {
            context = (ISCardContext) new SCardContext();
            context.Establish(SCardScope.System);
            releaseContextOnDispose = true;
        }

        this._context = context;
        this._reader = (ISCardReader) new SCardReader(context);
        this._releaseContextOnDispose = releaseContextOnDispose;
        this._disconnectReaderOnDispose = true;
    }

When, exception occur with message below:

System.DllNotFoundException: libpcsclite.so.1 assembly:<unknown assembly> type:<unknown type> member:(null)
  at (wrapper managed-to-native) PCSC.Interop.Linux.LinuxNativeMethods.SCardEstablishContext(intptr,intptr,intptr,intptr&)
  at PCSC.Interop.Linux.PCSCliteLinux.EstablishContext (PCSC.SCardScope dwScope, System.IntPtr pvReserved1, System.IntPtr pvReserved2, System.IntPtr& phContext) [0x00006] in C:\Users\danm\src\pcsc-sharp\src\PCSC\Interop\Linux\PCSCliteLinux.cs:39 
  at PCSC.SCardContext.Establish (PCSC.SCardScope scope) [0x00020] in C:\Users\danm\src\pcsc-sharp\src\PCSC\SCardContext.cs:81 
  at App1xx.Services.SimpleReader.SimpleReader..ctor (PCSC.ISCardContext context, System.Boolean releaseContextOnDispose) [0x00023] in C:\Users\vzhynkin\source\repos\App1xx\App1xx\App1xx\Services\SimpleReaderLib\SimpleReader.cs:59 
  at App1xx.Services.SimpleReader.SimpleReader..ctor () [0x00000] in C:\Users\vzhynkin\source\repos\App1xx\App1xx\App1xx\Services\SimpleReaderLib\SimpleReader.cs:70 
  at App1xx.Services.UaIdRLib.IdCardReader.connect () [0x00002] in C:\Users\vzhynkin\source\repos\App1xx\App1xx\App1xx\Services\UaIdRLib\IdCardReader.cs:371 
  at App1xx.Views.AboutPage.OnButtonClicked (System.Object sender, System.EventArgs args) [0x0000f] in C:\Users\vzhynkin\source\repos\App1xx\App1xx\App1xx\Views\AboutPage.xaml.cs:22 
  at Xamarin.Forms.Button.Xamarin.Forms.Internals.IButtonElement.PropagateUpClicked () [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Button.cs:187 
  at Xamarin.Forms.ButtonElement.ElementClicked (Xamarin.Forms.VisualElement visualElement, Xamarin.Forms.Internals.IButtonElement ButtonElementManager) [0x0001f] in D:\a\1\s\Xamarin.Forms.Core\ButtonElement.cs:61 
  at Xamarin.Forms.Button.SendClicked () [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Button.cs:173 
  at Xamarin.Forms.Platform.Android.ButtonElementManager.OnClick (Xamarin.Forms.VisualElement element, Xamarin.Forms.IButtonController buttonController, Android.Views.View v) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.Android\ButtonElementManager.cs:25 
  at Xamarin.Forms.Platform.Android.FastRenderers.ButtonRenderer.Android.Views.View.IOnClickListener.OnClick (Android.Views.View v) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.Android\FastRenderers\ButtonRenderer.cs:72 
  at Android.Views.View+IOnClickListenerInvoker.n_OnClick_Landroid_view_View_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_v) [0x00010] in /Users/builder/azdo/_work/278/s/xamarin-android/src/Mono.Android/obj/Release/monoandroid10/android-30/mcw/Android.Views.View.cs:2252 
  at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.68(intptr,intptr,intptr)

Does anyone faced with this issue?

Answer 1

The PCSC library does not appear to explicitly support Android. In my experience, nugets that work with Xamarin.Android have explicit dependencies set for the platform, but this one does not .

The library tries to use P/Invoke wrappers around native code. You can see that there are implementations for a number of operating systems here , but I don't see any references to Android. The stack trace shows that the code is deciding to use the Linux wrapper, which makes sense. It's looking for the libpcsclite.so.1 native "C/C++" library, but it's not finding it. That library has a home page that does not reference Android .

The PCSC nuget docs state:

pcsc-sharp does not contain any device drivers. A PC/SC compliant reader + driver is mandatory.

That's the libpcsclite.so.1 . Either your Android device doesn't provide it, or if it does, it's not in a location that your Android app can find it. My Android device (running Android 9) does not have that library in any of /system/*lib* directories, which means that at least for my device someone would need to compile that native library for the CPU (usually arm64) for the device. If you can either compile the native code yourself or find someone who has, AND the native code supports the reader on your Android device, then you could get the whole thing to work.

I don't have any experience with PCSC myself - just some experience with Xamarin and native libraries.