Try to doubly make sure that buffering and EGAIN doesn't interfere with communication

git-svn-id: https://svn.code.sf.net/p/xcat/code/xcat-core/trunk@16481 8638fb3e-16cb-4fca-ae20-7b5d299a9bcd

xCAT-server/sbin/xcatd

@@ -1055,6 +1055,9 @@ until ($quit) {
   }
   #we have a pending connection and we are under the threshold, grab one from the list and process it...
   my $cnnection=shift @pendingconnections;
+  my $previous = select ($cnnection); #assure that perl buffering is not in play at the low level
+  $|=1;
+  select ($previous);
   my $connection;
   my $child = xCAT::Utils->xfork(); #Yes we fork, IO::Socket::SSL is not threadsafe..
   if ($child) {
@@ -1099,6 +1102,9 @@ until ($quit) {
     unless ($connection) {
        xexit 0;
     }
+    $previous=select($connection); #also assure buffering not in play at SSL socket, which seems to be possibly independent of lower socket
+    $|=1;
+    select($previous);
     $clientselect->add($connection);
     my $peerhost=undef;
     my $peerfqdn=undef;
@@ -2137,7 +2143,9 @@ sub send_pending_responses {
                                 $blocks += 1;
                         }
                         foreach (0..$blocks) {
+                                do {
                                 syswrite($sock,$resp,4096,$_*4096);
+                                } while ($! == EAGAIN);
                         }
 	      	};
 }