use strict ; use warnings ;

  use IO::Handle ;
  use FileHandle ;
  use Scalar::Util qw(reftype) ;

  print "1________________________________\n",
        'open FH, ">&2" ;', "\n" ;
         open FH, ">&2" ;
    show('*FH', *FH) ;
    show('\*FH', \*FH) ;
    show('*FH{IO}', *FH{IO}) ;

  print "\n",
        "2________________________________\n",
        'open my $OUT, ">&2" ; ', "\n" ;
         open my $OUT, ">&2" ;
    show('$OUT', $OUT) ;
    show('*$OUT{IO}', *$OUT{IO}) ;

  print "\n",
        "3________________________________\n",
        'my $ih = new IO::Handle ;', "\n" ;
         my $ih = new IO::Handle ;
  print 'reftype($ih) = ', reftype($ih), "\n" ;
  print 'open $ih, ">&2" ;', "\n" ;
         open $ih, ">&2" ;
    show('$ih', $ih) ;
    show('*$ih{IO}', *$ih{IO}) ;

  print "\n",
        "4________________________________\n",
        'my $fh = new FileHandle ;', "\n" ;
         my $fh = new FileHandle ;
  print 'reftype($fh) = ', reftype($fh), "\n" ;
  print 'open $fh, ">&2" ;', "\n" ;
         open $fh, ">&2" ;
    show('$fh', $fh) ;
    show('*$fh{IO}', *$fh{IO}) ;

  sub show {
    my ($tag, $FH) = @_ ;

    my $can = $FH->can('autoflush') ? "can 'autoflush'" : "can NOT 'autoflush'" ;
    my $tst = defined(-t $FH) ? "OK" : 'undef' ;

    printf $FH "  show%-12s => %-18s fileno=%d  test=%-5s  %s\n",
               "($tag)", sex($FH), fileno($FH), $tst, $can ;
  } ;

  sub sex {
    my ($thing) = @_ ;
    my $sex = ref($thing) ;
    return $sex ? "ref:$sex" : ref(\$thing) ;
  } ;