only allow the host owner to restart dns

Reference: /n/atom/patch/applied2013/rdnsho
Date: Sun Jun 23 18:16:16 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /rc/bin/restartdns	Sun Jun 23 18:16:08 2013
+++ /rc/bin/restartdns	Sun Jun 23 18:16:08 2013
@@ -71,6 +71,11 @@
 	}
 }
 
+if(! ~ `{cat /dev/user} `{cat /dev/hostowner}){
+	echo 'restartdns: must be hostowner' >[1=2];
+	exit user
+}
+
 flagfmt='p,f'
 args=()
 if(! ifs=() eval `{aux/getflags $*} || ! ~ $#* 0){
@@ -104,7 +109,7 @@
 unmount '#s/dns_net.alt' /net.alt/dns >[2=]
 rm -f '#s/dns'  '#s/dns_net.alt'
 
-$dns -N 20000 -s
+$dns -N 30000 -s
 if(~ $sysname $recursive)
 	$dns -sx /net.alt -f /lib/ndb/external
 if not