I have char *array and it is dinamically alocated....
When I pass it to other function, I need to determine size of this array....
Problem: sizeof operator does not work with dinamically alocated
arrays!?!?!
How can I determine size of dinamically alocated array.... ?
Please advice...
Thx!
Mar 11 '06
32  2682 
Tomás wrote: Aren't all pointers the same? Same alignment, same amount of bits.
No.
We can use "void*" to store any sort of pointer... so it would make sense
if all pointer variables were the same.
A void* is large enough to store any pointer that can be implicitly
converted to void*.
Pointers to members are completely separate from void*.
Ben Pope
--
I'm not just a number. To many, I'm known as a string...
Ben Pope wrote: Pointers to members are completely separate from void*.
Pointers to members differ so completely from pointers that they should not
be called "pointers". They should be called "smart offsets", or
"discriminants" . Smart because they know if the target is virtual, offsets
because they know where in an object the target is, and discriminants
because they bind typesafely.
A pointer to member cannot be typecast.
--
Phlip http://www.greencheese.org/ZeekLand <-- NOT a blog!!!
In article <ut************ ******@news.ind igo.ie>, NU**@NULL.NULL says...
[ ... ] Aren't all pointers the same? Same alignment, same amount of bits.
Not necessarily. Just for one example, on a Cray a normal
address is of a 64-bit word. C and C++ use 8 bits for
char and 64 bits for everything else. A pointer to
anything else is basically a raw address, but a pointer
to char is an address _plus_ 3 extra bits to specify a
byte inside of that word.
We can use "void*" to store any sort of pointer... so it would make sense
if all pointer variables were the same.
It's also guaranteed that void * and char * have the same
representation -- but that's about it. An int * can be
(and as mentioned above, on at least one type of machine,
is) different.
--
Later,
Jerry.
The universe is a figment of its own imagination. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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