+
+/**
+ * Should we send the whole file as literal data rather than trying to
+ * create an incremental diff? This is on by default when both source
+ * and destination are local and we're not doing a batch delta,
+ * because there it's no cheaper to read the whole basis file than to
+ * just rewrite it.
+ *
+ * -1 means "unspecified", i.e. depend on is_local; 0 means off; 1 means on.
+ **/