.Fa answer
buffer with length
.Fa anslen
-supplied by the caller.
+supplied by the caller. Constants for
+.Fa type
+and
+.Fa class
+are defined in
+.Aq Pa arpa/nameser.h .
.Pp
The
.Fn res_search
entry
expands the compressed domain name
.Fa comp_dn
-to a full domain name
+to a full domain name.
The compressed name is contained in a query or reply message;
.Fa msg
is a pointer to the beginning of the message.