Re: TCHAR and buffer overflows

From: Edward Elliott (nobody@127.0.0.1)
Date: 08/26/02 

From: Edward Elliott <nobody@127.0.0.1>
Date: Mon, 26 Aug 2002 20:33:12 GMT

David Hopwood wrote:
> Edward Elliott wrote:
>>You don't think the sizeof(buf) expression is confusing?
>
> No, I don't. It gives the size of an object in bytes (for the C Standard
> definition of "byte"). It does not give the number of elements in an array.
> You *have* to understand this in order to have any chance of writing
> correct C code that uses sizeof.

_I_ understand that, and _you_ understand that, but programmers in
general obviously don't or these mistakes wouldn't occur. Part of the
confusion is the name, part is the common usage. If it were called
"byte_sizeof" or something, the problem would be more clear.

As it is, programmers often use sizeof for buffer sizes because they're
used to working with single-byte-char arrays. After a while, you may
incorrectly come to think of sizeof as the number of elements in the
array, when in fact that is just a happy coincidence of the fact that
you're using single-byte chars. This phenomenon is common enough at MS
at least to create many instances of the bug.

But arguing about what most programmers think is pointless. One of us
should conduct a random survey of programmers, or we should drop the issue. 

-- 
Edward Elliott

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