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Re: RFC - add snscanf(3) to stdio

> However, passing in a non-NULL terminated string is a bug.

C strings are not terminated with NULL; they are terminated with NUL.
Well, a zero byte, which is NUL if you're using something
ASCII-compatible, as NetBSD does.  (This is one of the reasons I
believe NULL should never be used.)

Passing a non-NUL-terminated string to sscanf is a bug.  It would not
be a bug for snscanf, which is much of the point of snscanf.  (As for
itohy's point, I think the parallel with sscanf is compelling enough to
justify the name even though it is not, strictly, accurate.)

Another benefit of snscanf, which I haven't seen mentioned yet, is that
it lets you scanf out of a "string" that contains nonterminal NULs,
much as you can fscanf out of a file containing NULs.

Yes, snscanf's lack can be worked around with fropen (or funopen), but
it's a bit ugly.  Perhaps people would be happer with an "fopen a block
of memory" call instead?

FILE *fopenmem(void * /*buf*/, int /*len*/, const char * /*mode*/);

or, for the sake of proper const poisoning, perhaps separate calls for
read and write?

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