[Tutor] Closing file objects when object is garbage collected?

[Tiger12506]

> I'm having issues when I test my software on XP, but not Linux. When I
> run the progam it fails after running for a while but not at exactly
> the same point each time. It fails in one of two ways, the user
> interface either completely disappears, or gives a OS error message
> unhanded exception error.

Could you give code for this, or provide a link?