Re: window-system and batch mode

[Richard Stallman]

    Yes, when I changed window-system to be terminal-local I had to decide
    what value to give to it for the initial "terminal" (which is basically
    just stdin/stdout rather than an X11 or tty connection).  I decided to
    use t (rather than nil which means "tty") to see what happens and
    hopefully catch some bugs.  And indeed it helped me get the
    "terminal-local window-system" patch working.

I am glad it helped catch some bugs, but the correct value for a stdin
is certainly nil.  stdin is not a window system.