Is there some limitation that makes having a --stdin option especially difficult for unoconv (Convert between any document format supported by OpenOffice) to support? It looks likes the file type is used to determine the document type so if standard input is used instead of a file name then the --doctype option would be required. But aside from this are there any other issues such as the way Uno is used? Uno (Universal Network Objects) is the component model of OpenOffice.org.