Thanks hiro.
Aladdin Ghostscript has been licensed to be included with the
release of Plan 9. Minor changes were made to the sources to
accommodate a couple of restrictions in the APE library and to
produce Plan 9 output formats. These changes are all conditioned
by
#ifdef Plan9
and were made in December, 1994. As well, the build was rearranged
to be driven by a Plan 9 mkfile.
After Realease 4 the ghostscript version was updated and in the folder cmd/gs/doc/public.html is part of the distribution and that isn't conforming to the MIT licence. 3 2 Restrictions makes commerical use without a written licence from Aladdin imposible.