In my role as convener of the ISO C++ committee, I get to field a number of questions about the committee and its process. It occurred to me that some of them might be of more general interest, so I’ll occasionally publish an edited version of my reply here in case other people have similar questions. Note that the quoted questions may be paraphrased.

Today’s question comes from someone who recently asked about why, if ISO C++ is an open standard, ISO charges for it and we can’t just download it for free.

The short answer is that people sometimes confuse “open” with “free.” ISO standards aren’t “open” like the O in FOSS, they’re “open” like “not developed behind closed doors.” Anyone who wants to pay for membership in their national body (if their country participates in ISO and in the specific project in question) is able to come join the fun. In free-as-in-beer terms, this means that experts are welcome to come to the ISO brewery at their own expense and volunteer their time to help brew the beer, and then when the beer is ready the customers still pay ISO to drink it (the helpers don’t get a cut of that, only a free bottle for their personal use and the satisfaction of having brewed a mighty fine keg).

Longer answer follows:

ISO C++ claims to be an OPEN STANDARD. Where can I download the OPEN STANDARD for ISO C++.

All published ISO standards are available for sale from the ISO store, via http://iso.org. You can purchase a copy of the latest currently published C++ standard, 14882:2003, here for CHF 380:

Also, your national standards body may sell a copy. For example, the ANSI store sells a PDF version here for US$ 30:

However, before you buy one of those, note that we’ve been actively working on a new revision to that standard, and hope to be done in the next year or so. You can get a free copy of the latest (but incomplete) draft of the C++ standard here:

Note that this is a working draft as of a couple of weeks ago; it is not the standard currently in force, and it is not exactly the standard that will be published in the next year or two, but it is a draft of the latter that’s in pretty good shape but will still get some editorial corrections and technical tweaks.

By the way, what does it mean, that the STANDARD of a widely used language is OPEN? Especially if I have to pay for it?

All ISO standards are "open standards" in that they’re developed in an open, inclusive process. All member nations of ISO are eligible to participate, send experts, contribute material, vote on ballots, and so forth. Additionally, some working groups, including C and C++, make all of their papers and all working drafts freely available on the web, as with the link above; the only thing a working group is not allowed to make freely available, except with special permission from ISO, is the text of the final standard it produces, because ISO reserves the right to charge for that.

Could you explain to me, what should it mean if the STANDARD of a widely used language was CLOSED?

Generally, that means it was developed privately by some closed industry group or consortium that not everyone is allowed to join and participate in. Some standards are developed behind closed doors controlled by some company or companies. ISO standards are not like that.

Best wishes,

Herb