The problem with this is that unless you pass a file or filehandle to write(), it doesn't actually return tarfile data (at least that's what I'm seeing in Archive::Tar's code) is that the actual data isn't returned, just the formatted listings. The actual routine to write the tar file is only called if you pass a reference to a filehandle or a filename. When I try passing in a reference to STDOUT, I get the same error as before (makes sense, they call the same internal routines).