-void xheader_string_begin (void);
-void xheader_string_add (char const *s);
-bool xheader_string_end (char const *keyword);
+void xheader_string_begin (struct xheader *xhdr);
+void xheader_string_add (struct xheader *xhdr, char const *s);
+bool xheader_string_end (struct xheader *xhdr, char const *keyword);