Other posters have answered why it doesn't work. But if you want to make it work: 
use FileHandle;

sub in { $_[0]->getline }
sub out { $_[0]->print(@_[1..$#_]) }

out \*STDOUT, in \*STDIN;

[download]
--Dave.

In reply to Re: $_[0] as a filehandle by dpuu
in thread $_[0] as a filehandle by jey

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