diff --git a/scheme/lib/dns.scm b/scheme/lib/dns.scm
index a08f76e..41dc2ea 100644
--- a/scheme/lib/dns.scm
+++ b/scheme/lib/dns.scm
@@ -1077,6 +1077,9 @@
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; Parsing of /etc/resolv.conf
 
+(define-condition-type 'resolv.conf-parse-error '(dns-error))
+(define resolv.conf-parse-error? (condition-predicate 'resolv.conf-parse-error))
+
 (define (parse-nameserver rest-of-line)
   (let ((match (regexp-search
 		(rx (: (submatch (** 1 3 digit) "."