Frank Thomas wrote:
How can I make the main window of my application unresizeable? (so that the
user can’t drag it at any corner)
You are going to need to tell us which GUI toolkit you’re using
(assuming we’re talking about a GUI application here 
For what it’s worth, if you’re using FXRuby, you do not want to pass
in the DECOR_RESIZE option to the main window’s new method. If you pass
in the DECOR_ALL option (as most or all of the FXRuby example programs
do), that includes DECOR_RESIZE.