So what is/was Mordecai Roshwald's day job?

OK, he wrote the classic “Level 7,” and one or two other lesser known books, but it seems unlikely that he lived of the royalties of “Level 7.” What did he do for a living, since it seems he was not exactly in the Isaac Asimov class of writing output?

(The chap might still be alive, thus the uncertainty in the title.)