another batch/pipe question...

Hello  group --

Recently there was a thread on the question of piping
or batching files to maxima --
I looked through it without resolving this question:

I had to revive some old code that worked on
Maxima 5.9.0 which included lines like this:

a3: limit(a2,theta,pi, MINUS);
nonzero;
positive;
positive;
positive;
positive;

which I used to invoke so

$ maxima < a16_1.mc

This doesn't work with Maxima 5.9.1;
instead the session hangs waiting for input, like this:
      2     2               2     2
Is  (z  + r2  - 2 r2 + 1) (z  + r2  + 2 r2 + 1)
positive or negative?

Even in 5.9.0, batch("...") gave the "wrong" behavior;
only the pipe worked, and now
that fails too.

Is there a workaround?

              Thanks,
                  Steve