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Question about scope of variables created with new

Lets say I have a program:

#include <iostream>
#include <conio.h>
using namespace std;

int* ptest();

int main()
{
int* b = ptest();
getch();

return 0;
}

int* ptest()
{
int num = 5;
int* intp = new int(num);

return intp;
}

Is there any way to free the memory that was allocated for the variable
intp outside of the function, ptest()? Thanks

Jul 23 '05
10 1488
Dave Vandervies wrote:
...and should be reset to NULL for safety

...even though it doesn't gain you much safety, unless you can be
absolutely certain that it's the only pointer to the just-deleted object
that exists.

But it only "survives" in that the pointer object[1] still exists and
you can point it at something else - the actual value of the pointer
can no longer be safely used.


And setting it to NULL keeps you from inadvertantly using the invalid
poitner. Unless they are going to be immediately destroyed, I don't
like leaving objects around that have indeterminate contents that will
cause undefined behavior if used.
Jul 23 '05 #11

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