Sorry for the off-topic post. I figured someone here would know the answer and I don't have access to Windows to check experimentally. The ocrad program opens its input like so: if ( std::strcmp( infile_name, "-" ) == 0 ) infile = stdin; else infile = std::fopen( infile_name, "r" ); (SpamBayes is starting to use ocrad and PIL to extract text from image spam). Ocrad fails on Windows because the input file is opened in text mode. That "r" should be "rb". What's not clear to me is whether we can do anything about stdin. Will this work: if ( std::strcmp( infile_name, "-" ) == 0 ) infile = std::fdopen( std::fileno(stdin), "rb" ); else infile = std::fopen( infile_name, "rb" ); That is, can I change stdin from text to binary this way or is it destined to always be in text mode? Thx, Skip