#Works
local *LOG;
open(LOG, '>>test.out');
openTee(*STDOUT, *STDOUT, *LOG); 

#Does not work
my $fh = IO::File->new(">>test.out");
openTee(*STDOUT, *STDOUT, *$fh);

#Does not work
open(my $fh, '>>', 'test.out');
openTee(*STDOUT, *STDOUT, *$fh);

#Does not work
open(my $fh, '>>', 'test.out');
openTee(*STDOUT, *STDOUT, *$fh);

#Works
openTee(*STDOUT, *STDOUT, '>>test.out');

#Works
openTee(*STDOUT, *STDOUT, 'test.out');