It is stupidly complicated to detect whether a given scalar is a filehandle (or
something filehandle like) in Perl. This module attempts to do so, but probably
falls short in some cases. The primary advantage of using this module is that it
gives you somebody to blame (me) if your code can't detect a filehandle.

The main use case for IO::Detect is for when you are writing functions and you
want to allow the caller to pass a file as an argument without being fussy as to
whether they pass a file name or a file handle.

WWW: http://search.cpan.org/dist/IO-Detect/