I know that when you call glVertexAttribPointer, you are specifying how the buffer currently binded should take its own data. But if you can have binded one buffer per type (Let's say GL_ARRAY_BUFFER and GL_ELEMENT_ARRAY_BUFFER) then, Are you specifying two buffers simultaneously? In this tutorial says:
glVertexAttribPointer always refers to whatever buffer is bound to GL_ARRAY_BUFFER at the time that this function is called. Therefore it does not take a buffer object handle; it simply uses the handle we bound previously.
If glVertexAttribPointer refers to the GL_ARRAY_BUFFER buffer currently binded, How I call glVertexAttribPointer for the GL_ELEMENT_ARRAY_BUFFER buffer?