C# mono p/invoke failure

Recently I tried to use p/invoke in mono (.NET for Linux platform) to write a simple OpenGL application to find out how it works on C# (I've already sucessfully done it on windows). I heard about the tao framework, but I don't want everything for a simple "hello world" like program.

I just stucked at the start. I p/invoked some GL functions to see if they work. I immediately called glClearColor and glClear to see whether it sets glGetError or not (due to opengl haven't been initialized at all at that point).

Instead of calling the function it just crashes and dumps the following stack trace and other debuginfo. No exception is thrown.

Stacktrace:

  at (wrapper managed-to-native) Calmarius.OGL.OpenGLLibrary.glClearColor (single,single,single,single) <0x00004>
  at (wrapper managed-to-native) Calmarius.OGL.OpenGLLibrary.glClearColor (single,single,single,single) <0xffffffff>
  at Calmarius.RTS.GameForm.OnPaint (System.Windows.Forms.PaintEventArgs) [0x00000] in /home/calmarius/Development/csharp/RTS/RTS/Form1.cs:60
  at System.Windows.Forms.Control.WmPaint (System.Windows.Forms.Message&) <0x000b0>
  at System.Windows.Forms.Control.WndProc (System.Windows.Forms.Message&) <0x001e2>
  at System.Windows.Forms.ScrollableControl.WndProc (System.Windows.Forms.Message&) <0x0000d>
  at System.Windows.Forms.ContainerControl.WndProc (System.Windows.Forms.Message&) <0x00054>
  at System.Windows.Forms.Form.WndProc (System.Windows.Forms.Message&) <0x001da>
  at ControlWindowTarget.OnMessage (System.Windows.Forms.Message&) <0x00014>
  at ControlNativeWindow.WndProc (System.Windows.Forms.Message&) <0x00022>
  at System.Windows.Forms.NativeWindow.WndProc (intptr,System.Windows.Forms.Msg,intptr,intptr) <0x001b7>
  at System.Windows.Forms.XplatUIX11.DispatchMessage (System.Windows.Forms.MSG&) <0x00016>
  at System.Windows.Forms.XplatUI.DispatchMessage (System.Windows.Forms.MSG&) <0x00015>
  at System.Windows.Forms.Application.RunLoop (bool,System.Windows.Forms.ApplicationContext) <0x00997>
  at System.Windows.Forms.Application.Run (System.Windows.Forms.ApplicationContext) <0x0006a>
  at System.Windows.Forms.Application.Run (System.Windows.Forms.Form) <0x00025>
  at Calmarius.RTS.Program.Main () [0x0000b] in /home/calmarius/Development/csharp/RTS/RTS/Program.cs:19
  at (wrapper runtime-invoke) System.Object.runtime_invoke_void (object,intptr,intptr,intptr) <0xffffffff>

The signature for glClearColor is:

//gllibname="opengl32.dll" --> mapped to libGL.so
[DllImport(gllibname)]

public static extern void glClearColor(float red, float green, float blue, float alpha);

C specification is:

void glClearColor( GLclampf red,GLclampf green,GLclampf blue,GLclampf alpha );

GLclampf is float as I saw its declaration in the header.

ansaurus

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C# mono p/invoke failure

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