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Jon.Cassorla wrote:
> 1) For a variable that is declared locally to a function of a 
>    structure
>    type, is the standard new constructor executed to allocated the
>    memory for the data structure?

No. You mustn't confuse "new" with "constructor". "new" allocates memory 
from the heap (and "delete" returns it). A constructor turns raw memory 
into a valid object (and a destructor turns it back into raw memory). 
Using "new" always calls a constructor if there is one (and "delete" 
always calls a destructor if there is one), but the opposite isn't true. 
If an object is static, it is allocated space by the 
compiler/linker/loader, constructed at the start of the program, and 
destroyed at the end. If an object is dynamic, it is allocated space on 
the stack, constructed when its declaration is executed, and destroyed 
when the containing block exits. Only if it is created in the heap with 
"new" does "operator new" get called.

> 2) When using "new" to allocate data space for a variable of a 
>    structure
>    type (ie no constructor defined), is the resulting memory space 
>    zero'd
>    out as a standard?

Nope, although there may be OSes that do this.

-- 

Ciao,
Paul D. DeRocco
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On 13 Mar 96 15:04:23 GMT, "Jon.Cassorla"
<cassorla@casey.columbiasc.ncr.com> wrote:

>1) For a variable that is declared locally to a function of a structure 
>   type, is the standard new constructor executed to allocated the 
>   memory for the data structure?

new is an operator not a constructor.  The non-overloaded form of
operator new allocates memory in which an object can be constructed.
After the memory is allocated, the object's ctor is called to build
the object from raw memory.

>2) When using "new" to allocate data space for a variable of a structure 
>   type (ie no constructor defined), is the resulting memory space zero'd
>   out as a standard?

No.

Jason
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