bin/sidekiqctl in sidekiq-4.0.0.pre2 vs bin/sidekiqctl in sidekiq-4.0.0

@@ -39,13 +39,17 @@
       done "Invalid command: #{stage}", :error
     end
   end
 
   def fetch_process
-    Process.getpgid(pid)
+    Process.kill(0, pid)
   rescue Errno::ESRCH
     done "Process doesn't exist", :error
+  # We were not allowed to send a signal, but the process must have existed
+  # when Process.kill() was called.
+  rescue Errno::EPERM
+    return pid
   end
 
   def done(msg, error = nil)
     puts msg
     exit(exit_signal(error))
@@ -65,13 +69,15 @@
 
   def stop
     `kill -TERM #{pid}`
     kill_timeout.times do
       begin
-        Process.getpgid(pid)
+        Process.kill(0, pid)
       rescue Errno::ESRCH
         FileUtils.rm_f pidfile
         done 'Sidekiq shut down gracefully.'
+      rescue Errno::EPERM
+        done 'Not permitted to shut down Sidekiq.'
       end
       sleep 1
     end
     `kill -9 #{pid}`
     FileUtils.rm_f pidfile