+/* Listmaker that takes a format string and args for the element.
+Currently no checking of the element content for sep chars */
+
+gstring *
+string_append_listele_fmt(gstring * list, uschar sep, const char * fmt, ...)
+{
+if (list && list->ptr)
+ list = string_catn(list, &sep, 1);
+
+va_list ap;
+va_start(ap, fmt);
+list = string_vformat_trc(list, US __FUNCTION__, __LINE__,
+ STRING_SPRINTF_BUFFER_SIZE, SVFMT_REBUFFER|SVFMT_EXTEND, fmt, ap);
+va_end(ap);
+
+(void) string_from_gstring(list);
+return list;
+}
+
+