| Date: Sat, 30 Oct 2010 18:02:59 -0400
 | From: "Aaron W. Hsu" <arcfide-5nC73gNclPNzbRFIqnYvSA@public.gmane.org>
 |
 | Nonetheless, how would file descriptors being visible inherently
 | lead to leaks?

If the way you refer to file-descriptors is by number, then there is
no way for the garbage collector to prove that a file-descriptor is no
longer in use.

If the garbage collector can't reclaim file-descriptors, then it
becomes the programmer's responsibility to close file-descriptors it
no longer uses.  Exceptions or programmer oversights result in leaked
file-descriptors.