9.2 The default terminal
The default terminal is normally X11_singleWindow. There are two exceptions to this. When Pyxplot is not called from within an X11 session1, and it therefore cannot open graphical display windows, the default terminal changes to eps. When Pyxplot is used non-interactively – i.e. one or more command scripts are specified on the command line, and Pyxplot exits as soon as it finishes executing them – the X11_persist terminal becomes default, since it does not close plot windows when Pyxplot exits.