Clarification on Free and Payed C standard specification

Question

I found (in http://c-faq.com/ansi/avail.html) that "An electronic (PDF) copy is available on-line, for US$18, from www.ansi.org".

But at the same time, I can download it for free from http://www.open-std.org/JTC1/sc22/wg14/www/docs/n1256.pdf

Both are C standards, right ? What is the difference between two ?

Answer 1

The latter is a draft. Accurate and containing everything you need, but in draft form.

This is a WG14 working paper, but it reflects the consolidated standard at the time of issue

Answer 2

All the documents like n1234 are draft versions of the standards. If you want the real, published versions, you have to buy them from your local standards organisation.

That's rarely necessary unless you're Microsoft, Borland/Unprized/Enchilada (or whatever they call themselves nowadays), IBM or some other compiler writer. Normal people get by quite adequately on the late-edition drafts just fine.

Answer 3

The latest draft, dubbed C1X, and approved for publication, is http://www.open-std.org/JTC1/sc22/wg14/www/docs/n1548.pdf. This is probably as close to the next standard as you will be able to get without paying for the formalized version. Better to take that version, since n1256 missed several clarifications and corrections.