Models proper exit

Use atomics to signal controller code should exit, instead of sleep and assume approach.

src/epics/util/lib/Parser3.pm

@@ -643,7 +643,7 @@ sub node_processing {
 		return 1; # Do not call this function on leaves, we already did that
 	} elsif ($block_type eq "Reference") {
                 if ($source_block =~ /cdsIPCx/) {
-                   if ($block_name !~ /[CGHKLMSX]\d\:/) {
+                   if ($block_name !~ /[A-Z]\d\:/) {
                       die "***ERROR: Signal name of IPCx module must include IFO: $block_name\n";
                    }
                 }