int (*output_fn) (const char *, PRInt32, void *),
nsresult (*output_fn) (const char *, PRInt32, void *),
mime_encoder_init (mime_encoding which,				   int (*output_fn) (const char *, PRInt32, void *),				   void *closure){  MimeEncoderData *data = PR_NEW(MimeEncoderData);  if (!data) return 0;  memset(data, 0, sizeof(*data));  data->encoding = which;  data->write_buffer = output_fn;  data->closure = closure;  return data;}