At 1:18 PM -0500 2/14/00, [EMAIL PROTECTED] wrote:
>typedef struct
>{
> Byte n;
> UInt i;
> char text[1];
>} PackedStruct
>
>...
>
>What I do when I need to know the amount of memory to allocate for a packed struct is
>something like
>
>memneeded = (sizeof(PackedStruct) - 1) + StrLen(str1) + StrLen(str2) + ... +
>numstrings;
>
>The -1 takes off the size of the single char placeholder at the end of the struct,
>and numstrings accounts for null terminators on each string.
Here's a question for all you C gurus out there: What is the size of a struct that
contains an unbounded array? This is the only question about C I couldn't find the
answer to in Harbison & Steele's book.
typedef struct
{
...
SomeType finalField[];
} MyStruct
... sizeof(MyStruct) ...
So what is the size of this struct? The answer, in practice, seems to be that the
final field is considered to be of size zero. (Of course, there can be padding before
the final field, but that isn't the issue.) I have never seen a book on C that
explains this. Perhaps this is why some programmers use char text[1] instead of char
text[]?
-
Danny Epstein - Applied Thought
No Palm is an Island - try BeamBooks
http://www.appliedthought.com/beambooks
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