Index: configure.ac
==================================================================
--- configure.ac
+++ configure.ac
@@ -1521,10 +1521,25 @@
 	])
 	AC_CHECK_MEMBER(struct sockaddr_un.sun_path, [
 		AC_DEFINE(OF_HAVE_UNIX_SOCKETS, 1,
 			[Whether we have UNIX sockets])
 		AC_SUBST(USE_SRCS_UNIX_SOCKETS, '${SRCS_UNIX_SOCKETS}')
+
+		AC_CHECK_MEMBERS(struct sockaddr_un.sun_len, [], [], [
+			#ifdef OF_HAVE_SYS_TYPES_H
+			# include <sys/types.h>
+			#endif
+			#ifdef OF_HAVE_SYS_UN_H
+			# include <sys/un.h>
+			#endif
+			#ifdef _WIN32
+			# include <winsock2.h>
+			#endif
+			#ifdef HAVE_AFUNIX_H
+			# include <afunix.h>
+			#endif
+		])
 	], [], [
 		#ifdef OF_HAVE_SYS_TYPES_H
 		# include <sys/types.h>
 		#endif
 		#ifdef OF_HAVE_SYS_UN_H

Index: src/OFSocket.m
==================================================================
--- src/OFSocket.m
+++ src/OFSocket.m
@@ -588,10 +588,13 @@
 	memset(&ret, '\0', sizeof(ret));
 	ret.family = OFSocketAddressFamilyUNIX;
 	ret.length = (socklen_t)
 	    (offsetof(struct sockaddr_un, sun_path) + length);
 
+#ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
+	ret.sockaddr.un.sun_len = (uint8_t)length;
+#endif
 #ifdef AF_UNIX
 	ret.sockaddr.un.sun_family = AF_UNIX;
 #else
 	ret.sockaddr.un.sun_family = AF_UNSPEC;
 #endif