Use Rex.sleep :-)

"Right is right even if no one is doing it; wrong is wrong even if everyone is doing it"

user@x:/opt/metasploit$ grep -nr "select(nil, nil, nil" . | wc -l
189
user@x:/opt/metasploit$ grep -nr "Rex.sleep" . | wc -l
25

Author: 0a2940

modules/exploits/linux/local/pkexec.rb

@@ -348,7 +348,7 @@ def exploit
     stime = Time.now.to_f
     print_status "Starting the payload handler..."
     until session_created? || stime + datastore['ListenerTimeout'] < Time.now.to_f
-      select(nil, nil, nil, 1)
+      Rex.sleep(1)
     end
   end
 end