Using Eclipse + Texlipse (LaTeX plugin) on Ubuntu 11.04 -- though it should apply to other OSs too.
In the project explorer, double clicking on a PDF file will open it with the "System Editor" or "Default Editor". In practise, if I double click a PDF it gets opened by Adobe Reader, while my default PDF reader is different (Okular in my case).
Where does Eclipse get the information about the default editor/viewer?
I'm aware there is a "Preview Document" button in Texlipse that can be customised to use any viewer, but I'm just trying to understand how Eclipse works.