Original patch from: gentoo/src/patchsets/glibc/2.9/1055_all_glibc-resolv-dynamic.patch

-= BEGIN original header =-

ripped from SuSE

if /etc/resolv.conf is updated, then make sure applications

already running get the updated information.

http://bugs.gentoo.org/177416

-= END original header =-

diff -durN glibc-2_9.orig/resolv/res_libc.c glibc-2_9/resolv/res_libc.c

--- glibc-2_9.orig/resolv/res_libc.c	2006-10-11 10:59:28.000000000 +0200

+++ glibc-2_9/resolv/res_libc.c	2009-02-02 22:00:57.000000000 +0100

@@ -22,6 +22,7 @@

 #include <arpa/nameser.h>

 #include <resolv.h>

 #include <bits/libc-lock.h>

+#include <sys/stat.h>

 /* The following bit is copied from res_data.c (where it is #ifdef'ed

@@ -95,6 +96,20 @@

 __res_maybe_init (res_state resp, int preinit)

 {

 	if (resp->options & RES_INIT) {

+		static time_t last_mtime, last_check;

+		time_t now;

+		struct stat statbuf;

+		

+		time (&now);

+		if (now != last_check) {

+			last_check = now;

+			if (stat (_PATH_RESCONF, &statbuf) == 0 && last_mtime != statbuf.st_mtime) {

+				last_mtime = statbuf.st_mtime;

+				atomicinclock (lock);

+				atomicinc (__res_initstamp);

+				atomicincunlock (lock);

+			}

+		}

 		if (__res_initstamp != resp->_u._ext.initstamp) {

 			if (resp->nscount > 0) {

 				__res_iclose (resp, true);