Maybe a partial solution: if your stream is actually just a scalar (e.g. in variable $body), then you may treat is as a file handle via IO::Scalar. If the method you'd like to call accepts a filehandle, this does the trick:

use strict;
use IO::Scalar;

my $body = &get_body(); # whatever...
my $handle = new IO::Scalar($body);

# now call the method that expects a file handle
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I used this succesfully on XML::Simple, which can be instantiated with either a filename or a filehandle. If your module really only groks filenames, then you're out of luck and may need to revert to a tempfile of some kind.

HTH!

--
Cheers, Joe