__ptr32, __ptr64
Microsoft Specific
__ptr32
represents a native pointer on a 32-bit system, while __ptr64
represents a native pointer on a 64-bit system.
The following example shows how to declare each of these pointer types:
int * __ptr32 p32;
int * __ptr64 p64;
On a 32-bit system, a pointer declared with __ptr64
is truncated to a 32-bit pointer. On a 64-bit system, a pointer declared with __ptr32
is coerced to a 64-bit pointer.
Note
You cannot use __ptr32
or __ptr64
when compiling with /clr:pure. Otherwise, Compiler Error C2472 will be generated. The /clr:pure and /clr:safe compiler options are deprecated in Visual Studio 2015 and unsupported in Visual Studio 2017.
For compatibility with previous versions, _ptr32 and _ptr64 are synonyms for __ptr32
and __ptr64
unless compiler option /Za (Disable language extensions) is specified.
Example
The following example shows how to declare and allocate pointers with the __ptr32
and __ptr64
keywords.
#include <cstdlib>
#include <iostream>
int main()
{
using namespace std;
int * __ptr32 p32;
int * __ptr64 p64;
p32 = (int * __ptr32)malloc(4);
*p32 = 32;
cout << *p32 << endl;
p64 = (int * __ptr64)malloc(4);
*p64 = 64;
cout << *p64 << endl;
}
32
64
END Microsoft Specific