read pixels from back buffer

[vivendi]

I want to read the pixels from the back buffer. But all i get so far is a black screen (the clear color).

The thing is, is that i don't need a glut window to draw to. Once i have the pixel information, then i pass that to another program which will draw the image for me.

My init function looks like this:

	char fakeParam[] = "nothing"; 
	char *fakeargv[] = { fakeParam, NULL }; 
	int fakeargc = 1; 

	glutInit( &fakeargc, fakeargv );
	GLenum err = glewInit();

	if (GLEW_OK != err)
	{
		MessageBoxA(NULL, "Failed to initialize OpenGL", "ERROR", NULL);
	}
	else
	{
		glEnable(GL_TEXTURE_2D);
		glEnable(GL_DEPTH_TEST);

		// Not sure if this call is needed when i don't use a glut window to render too...
		glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);

	}

Then in my render function i do:

void DisplayFunc(void)
{
  static float alpha = 0;

  /* Clear the buffer, clear the matrix */
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  glLoadIdentity();

// TEAPOT
glTranslatef(0.0f, 0.0f, -5.0f); // Translate back 5 units
glRotatef(rotation_degree, 1.0f, 1.0f, 0.0f); // Rotate according to our rotation_degree value

glFrontFace(GL_CW);
glutSolidTeapot(1.0f); // Render a teapot
glFrontFace(GL_CCW);

glReadBuffer(GL_BACK);
glReadPixels(0, 0, (GLsizei)1024, (GLsizei)768, GL_RGB, GL_UNSIGNED_BYTE, pixels);
}

This is basically all i do. At the end of the last function is where i'm trying to read all the pixels. But the output is just a black image.

Anyone any idea what i'm doing wrong...??