void pointer

Niks

what is a void pointer?

Sep 7 '05 #1

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7239

Jim Langston

"Niks" <nb*****@gmail.com> wrote in message
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what is a void pointer?

void* MyPointer;

Sep 7 '05 #2

Victor Bazarov

Niks wrote:

what is a void pointer?

You mean a pointer to void?

A generic pointer, a plain address. That type is returned from 'malloc'
function and from 'operator new', and is accepted by 'operator delete'
as an argument. Usually a pointer to void is used to hold a pointer to
an object of any type or of an unknown type. Has the same alignment
requirements and the same representation as 'char*'. Along with the
requirement that 'void*' can hold a pointer to any object comes the
standard conversion from a pointer to object to a pointer to void. That
conversion is implicit and the reverse can be done using 'static_cast'.

V

Sep 7 '05 #3

Dan Cernat

Victor Bazarov wrote:

Niks wrote:
what is a void pointer?

You mean a pointer to void?

A generic pointer, a plain address. That type is returned from 'malloc'
function and from 'operator new', and is accepted by 'operator delete'
as an argument. Usually a pointer to void is used to hold a pointer to
an object of any type or of an unknown type. Has the same alignment
requirements and the same representation as 'char*'. Along with the
requirement that 'void*' can hold a pointer to any object comes the
standard conversion from a pointer to object to a pointer to void. That
conversion is implicit and the reverse can be done using 'static_cast'.

V

Can it hold (is it big enough to hold) a pointer to a member function?
I know that the pointers to member functions are implementation
specific, but I was wondering if the standard says anything about this.

thanks,
Dan

Sep 7 '05 #4

Victor Bazarov

Dan Cernat wrote:

Victor Bazarov wrote:
Niks wrote:
what is a void pointer?
You mean a pointer to void?

A generic pointer, a plain address. That type is returned from 'malloc'
function and from 'operator new', and is accepted by 'operator delete'
as an argument. Usually a pointer to void is used to hold a pointer to
an object of any type or of an unknown type. Has the same alignment
requirements and the same representation as 'char*'. Along with the
requirement that 'void*' can hold a pointer to any object comes the
standard conversion from a pointer to object to a pointer to void. That
conversion is implicit and the reverse can be done using 'static_cast'.

V

Can it hold (is it big enough to hold) a pointer to a member function?

No. Only a pointer to an object.
I know that the pointers to member functions are implementation
specific, but I was wondering if the standard says anything about this.

It says "A void* shall be able to hold any object pointer."

V

Sep 7 '05 #5

Dan Cernat

Victor Bazarov wrote:

Dan Cernat wrote:
Victor Bazarov wrote:
[...]
It says "A void* shall be able to hold any object pointer."

V

Thanks,
Dan

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