Fixed a null pointer exception.

lib/modules/Filesystem.pmod/Monitor.pmod/basic.pike

@@ -996,15 +996,18 @@ protected void inotify_event(int wd, int event, int cookie, string(8bit) path)
 	//
 	// Create the submonitor.
 	MON_WARN("Monitor lost for path %O.\n", full_path);
-	monitor(full_path, m->flags | MF_AUTO | MF_HARD,
+        m = monitor(full_path, m->flags | MF_AUTO | MF_HARD,
             m->max_dir_check_interval,
             m->file_interval_factor,
             m->stable_time);
-	m = monitors[full_path];
+        // monitor() will not register monitor for path if filter_file()
+        // returns 0.
+        if (m) {
           m->check(0);    // Init monitor.
         }
       }
     }
+  }
 
   if (m) {
     if (event == System.Inotify.IN_IGNORED) {
@@ -1325,7 +1328,7 @@ protected DefaultMonitor monitor_factory(string path, MonitorFlags|void flags,
 //!
 //! @seealso
 //!   @[release()]
-void monitor(string path, MonitorFlags|void flags,
+Monitor|void monitor(string path, MonitorFlags|void flags,
 	     int(0..)|void max_dir_check_interval,
 	     int(0..)|void file_interval_factor,
 	     int(0..)|void stable_time)
@@ -1356,6 +1359,7 @@ void monitor(string path, MonitorFlags|void flags,
     // NB: Registering with the monitor_queue is done as
     //     needed by register_path() as called by create().
   }
+  return m;
 }
 
 int filter_file(string path)