cleanUp();

function cleanUp() {
     //
     // Initial cleanup: Close all windows.
     //   This should recover as much memory as possible.  It also ensures
     //   the Results and Log windows are emptied.
     //   What to do about other text windows?  For now, just hope they're small...
     //
     write( "Closing Results window." );      // Force Results window to exist, since...
     selectWindow("Results");      // ... this crashes if window is absent.
     run( "Close" );
     print( "Closing Log window.");     // Force Log window to exist, since...
     selectWindow("Log");                // ... this crashes if window is absent.
     run( "Close" );
     while (nImages()>0) {
          selectImage(nImages());      // This can crash when more than a couple large stacks exist, and we don't wait for GUI to finish.
          run("Close");
    }
}