On 11/23/07, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> "Marko Kreen" <markokr@gmail.com> writes:
> > On 11/23/07, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> Why? I can't imagine any real use for it. If you're thinking that
> >> it could provide a guide as to what to resize the buffer to, think
> >> again.
>
> > If the output was truncated due to this limit then the return
> > value is the number of characters (not including the trailing
> > '\0') which would have been written to the final string if
> > enough space had been available.
>
> > What problem do you see?
>
> The problem is that you are quoting from some particular system's
> manual, and not any kind of standard ... much less any standard that
> every platform we support follows.
>
> The real-world situation is that we are lucky to be able to tell
> vsnprintf success from failure at all :-(
Ah, ok.
I just saw the result used inside the function, so I thought
it is standard enough.
Actually, the meaning could be changed to *needmore
and compensated inside function:
*needmore = (nprinted < buf->maxlen) ? buf->maxlen : nprinted + 1;
Then it would not matter if libc is conforming or not.
--
marko