getting dirhandles and formats from *foo

[Jeff Pinyan <jeffp@crusoe.net>]

Hey, while brushing up on typeglobs, I figured out how to determine if a
filehandle has been brought into being yet:

  print defined *FOO{IO};

However, *FOO{IO} only works for filehandles and dirhandles.  And about
those dirhandles... I note IO::Handle doesn't appear to be /about/
dirhandles at all -- I didn't see any related methods.  However, doing:

  opendir A, ".";
  open B, "foo";
  print defined(*A{IO}) ? 1 : 0;
  print defined(*B{IO}) ? 1 : 0;
  print defined(*C{IO}) ? 1 : 0;

prints 110, as expected.  I guess part of the hassle is that filehandles,
dirhandles, and formats are not "top-level" Perl objects, as are scalars,
arrays, hashes, subroutines...

I'm puzzled at how to get formats out of a glob. :)  I guess, though, it's
not needed at all.

-- 

  MIDN 4/C PINYAN, USNR, NROTCURPI     http://www.pobox.com/~japhy/
  jeff pinyan: japhy@pobox.com     perl stuff: japhy+perl@pobox.com
  CPAN ID: PINYAN  http://www.perl.com/CPAN/authors/id/P/PI/PINYAN/
  PerlMonth - An Online Perl Magazine     http://www.perlmonth.com/

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