ref: d5fc608059dee5f65ddfdf3e230bb8d458ccf43f
dir: /sys/src/cmd/postscript/postreverse/README/
A simple program that reverses the pages in PostScript files that conform to Adobe's Version 1.0 or Version 2.0 file structuring conventions. postrevese also handles a small class of files that violate page independence (eg. output from dpost) and can be used with all the translators in this package. The output can be conforming even if the input file wasn't.