Thread: sizeof dynamic allocation

When i allocate dynamically a char* of 256 array for example, i thought that its size is 256 bytes.
But sizeof() always gives back the size of a char*.
So how would i go to get the size allocated?

Code:

#include <iostream>

using namespace std;

int  main()
{
    char * buf = new char[256];
    cout << sizeof(buf) <<"\n";
    delete [] buf;
   
    return  0;
}