I am using the
a2ps utility from Homebrew to pretty print code, generating
.ps files, and then the Mac OS X utility
pstopdf (used by Preview.app) to convert these to
a2ps --medium=A4 -P file myfile.py
a2ps --medium=A3 -P file myfile.py
generate PostScript files with the correct page dimensions (A4 and A3 respectively) but when converted to PDF by
pstopdf the resulting PDF is Letter size with the output truncated at the right/ bottom edge of the page.
I can't find any mention anywhere of how to specify what default page size
pstopdf uses. Opening the PostScript files in Preview.app uses
pstopdf in the back end so I get the same result.