Re: Are bad developer libraries the problem with M$ software?

Ali Saifullah Khan wrote:

> Here is a test done on the return of sizes by sizeof() using pointers.

No, 4096 is definitely correct for an architecture with 32-bit pointers.

> Apparently, using a pointer has multiplied the value of the original size of

You have declared testbuff as an array of 1024 pointers to character. Each pointer is 4 bytes, so the array occupies 4096 bytes.

If you had instead used:

        char (*testbuff)[1024];

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then testbuff would be a pointer to an array of 1024 characters, so sizeof(testbuff) would be 4, and sizeof(*testbuff) would be 1024. Note, however, that (testbuff + 1) would point at memory 1024 bytes further on than testbuff itself (i.e. one array of 1024 characters further on).

OTOH, if you had just used:

        char testbuff[1024];

then sizeof(testbuff) would be 1024. However, in most contexts, the symbol "testbuff" would be implicitly cast to a pointer to character, as if you had written &testbuff[0]. Then, sizeof(&testbuff[0]) would be 4.

All of this is adequately explained in chapter 5 of K&R, BTW.

> char pointers have a size of 4 bytes.....as is shown when output is 4 bytes

Not at all strange, once you understand C (in particular, the syntax of data declarations).

-- 
Glynn Clements