If OpenSimulator is writing a PID file and finds the file already present on startup, logging an error since this is commonly due to an unclean shutdown.

Unclean shutdown can cause constantly moving objects to disappear if an OAR has just been loaded and they have not reached persistence time threshold, among other problems.

OpenSim/Framework/Servers/ServerBase.cs

@@ -76,6 +76,11 @@ namespace OpenSim.Framework.Servers
 
         protected void CreatePIDFile(string path)
         {
+            if (File.Exists(path))
+                m_log.ErrorFormat(
+                    "[SERVER BASE]: Previous pid file {0} still exists on startup.  Possibly previously unclean shutdown.", 
+                    path);
+
             try
             {
                 string pidstring = System.Diagnostics.Process.GetCurrentProcess().Id.ToString();