ps-spool-tumble

ps-spool-tumble is a variable defined in `ps-print.el'.
Its value is

nil

Documentation:
Specify how the page images on opposite sides of a sheet are oriented.
If `ps-spool-tumble' is nil, produces output suitable for binding on the left
or right. If `ps-spool-tumble' is non-nil, produces output suitable for
binding at the top or bottom.

It has effect only when `ps-spool-duplex' is non-nil.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 20 of Emacs.