diff -urN ffingerd-1.28.org/ffingerd.c ffingerd-1.28/ffingerd.c
--- ffingerd-1.28.org/ffingerd.c        Sun Aug 12 17:34:04 2001
+++ ffingerd-1.28/ffingerd.c    Sun Aug 12 17:35:50 2001
@@ -72,6 +72,11 @@
 #define PATH_MAX 256
 #endif

+#ifndef SA_LEN
+#define SA_LEN(x) (((x)->sa_family == AF_INET6)?sizeof(struct sockaddr_in6): \
+       (((x)->sa_family == AF_INET)?sizeof(struct sockaddr_in):sizeof(struct sockaddr)))
+#endif
+
 #ifdef __STDC__
 void dump_file(char *filename,char *found_message,char *not_found_message) {
 #else