/*
* An example of MimeInfo structure:
*
- * multipart/mixed root <-+ parent
- * |
- * multipart/alternative children <-+ parent
- * |
- * text/plain children --+
- * |
- * text/html next <-+
- *
- * message/rfc822 next <-+ main
- * |
- * sub (capsulated message)
- *
- * image/jpeg next
+ * 1: +- message/rfc822 (root)
+ * |
+ * 2: +- multipart/mixed (children of 1)
+ * | |
+ * 3: | +- multipart/alternative (children of 2)
+ * | | |
+ * 4: | | +- text/plain (children of 3)
+ * | | |
+ * 5: | | +- text/html (next of 4)
+ * | |
+ * 6: | +- message/rfc822 (next of 3)
+ * | |
+ * 7: | ... (children of 6)
+ * |
+ * 8: +- image/jpeg (next of 2)
*/
struct _MimeInfo