Check for -lresolv for Darwin.

configure

@@ -6726,6 +6726,79 @@ _ACEOF
 
 fi
 
+
+echo "$as_me:$LINENO: checking for res_9_init in -lresolv" >&5
+echo $ECHO_N "checking for res_9_init in -lresolv... $ECHO_C" >&6
+if test "${ac_cv_lib_resolv_res_9_init+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lresolv  $LIBS"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+/* Override any gcc2 internal prototype to avoid an error.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+/* We use char because int might match the return type of a gcc2
+   builtin and then its argument prototype would still apply.  */
+char res_9_init ();
+int
+main ()
+{
+res_9_init ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
+  (eval $ac_link) 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+	 { ac_try='test -z "$ac_c_werror_flag"			 || test ! -s conftest.err'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } &&
+	 { ac_try='test -s conftest$ac_exeext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  ac_cv_lib_resolv_res_9_init=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ac_cv_lib_resolv_res_9_init=no
+fi
+rm -f conftest.err conftest.$ac_objext \
+      conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+echo "$as_me:$LINENO: result: $ac_cv_lib_resolv_res_9_init" >&5
+echo "${ECHO_T}$ac_cv_lib_resolv_res_9_init" >&6
+if test $ac_cv_lib_resolv_res_9_init = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBRESOLV 1
+_ACEOF
+
+  LIBS="-lresolv $LIBS"
+
+fi
+
 echo "$as_me:$LINENO: checking for pthread_create in -lpthread" >&5
 echo $ECHO_N "checking for pthread_create in -lpthread... $ECHO_C" >&6
 if test "${ac_cv_lib_pthread_pthread_create+set}" = set; then

configure.ac

@@ -140,6 +140,8 @@ dnl Check for -lxpg4 for FreeBSD
 AC_CHECK_LIB(xpg4,_xpg4_setrunelocale)
 dnl Check for -lpoll for Mac OS X/Darwin
 AC_CHECK_LIB(poll,poll)
+dnl Check for -lresolv for Mac OS X/Darwin
+AC_CHECK_LIB(resolv,res_9_init)
 dnl Check for -lpthread
 AC_CHECK_LIB(pthread,pthread_create,AC_SUBST(LIBPTHREAD,"-lpthread"))