RE: ANSI C and POSIX (was Re: C/C++ knocks the crap out of Ada)

[Bradd W. Szonye <bradds@ix.netcom.com>]

On Saturday, April 13, 1996, Robert Dewar wrote...
> "If the project managers want to use software standards to help
> ensure portability, there's no barrier I'm aware of that keeps
> them from using standard semantics for the system-independent
> parts of their projects.  In many cases this greatly reduces
> porting effort for most of the source."
> 
> I completely agree with Chuck Karish on this. Clear specifications from
> appropriate software standards, which are well understaood and carefully
> followed by all programmers, without reference to "unwritten rules"
> and "sensible reasoning", are a huge help in making programs easily
> portable. If anyone can remember back far enough :-) this is the point
> that I was originally making with respect to the read function!
> 
> Note however that this is not sufficient to guarantee portability. For
> simple programs that can be made 100% portable, then indeed carefully
> following standards is a key. In this regard, I far prefer national
> and international standards to industry standards, since the former
> have typically gone through a much more intensive review, and are
> more stable (I preer that ISO owns a standard and is the only one
> who can change it, than that the standard be owned by the "current
> holder of the copyright", whose interests are fundamentally commercial
> ones which may even be at odds with the basic goals of standardization).
> 
> However, many large programs have sections that cannot be written
> in a portable manner, and here the issue is very careful isolation
> and documentation of these sections of code.
> 
> In my experience many portability problems are caused by programmers
> not understanding the relevant standards well. How many C++ programmers
> have read the proposed draft standard. FOr that matter how many C
> programmers have read the ANSI standard for C. One problem is that
> these standards are often remarkably inaccessible, and/or expensive.
> It certainly would be nice if other languages and systems could follow
> the lead of Ada, and make their standards freely available over the net.
> The POSIX standard has, at least in the past, been problematical from
> this point of view.
> 
> 

The standards are a lot more accessible now with the increased popularity
of the Internet. I've read both standards, and the bigger problem is the
inaccessible legalese of the standards themselves, which are written for
compiler vendors, *not* programmers.

Pick up Schildt's "Annoted ANSI C Standard" and Plauger/Brodie's "Standard
C: A Reference". Between the two they cover the original standard and
Amendment 1 fairly well.

You can get the April 1995 C++ papers from AT&T's Web site in PostScript
format, and from several other sites in HTML. Other sites typically have
the (confidential) September 1995 papers. You can find them fairly easily
with Infoseek: [C++ standard] ANSI ISO

Bradd