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5.34: How do I dup() a filehandle in Perl?

If you check "open" in perlfunc, you'll see that several of the ways to
call open() should do the trick. For example:

open my $log, '>>', '/foo/logfile';
open STDERR, '>&LOG';

Or even with a literal numeric descriptor:

open $mhcontext, "<&=$fd"; # like fdopen(3S)

Note that "<&STDIN" makes a copy, but "<&=STDIN" make an alias. That
means if you close an aliased handle, all aliases become inaccessible.
This is not true with a copied one.

Error checking, as always, has been left as an exercise for the reader.


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