A simple program used to test new handler.

test_new_handler.cpp

#include <iostream>
#include <unistd.h>
#include <cstring>
#include <new>

using namespace std;


struct ListNode
{
    ListNode()
        : next(NULL)
    {}

    ListNode* next;
    char data[1024 * 1024 * 512]; // 512M
};

ListNode* front;


void NewHandler()
{
    const char* msg = "NewHandler is called\n";
    write(2, msg, strlen(msg));

    ListNode* cur = NULL;
    while (front != NULL)
    {
        cur = front;
        front = front->next;
        delete cur;
    }
}


int main(int argc, char *argv[])
{
    set_new_handler(&NewHandler);
    const char* msg = "new handler is set\n";
    write(2, msg, strlen(msg));

    int count = 0;
    ListNode** node = &front;
    while (true)
    {
        *node = new ListNode;
        node = &((*node)->next);
        ++count;
        if (count % 2 == 0)
        {
            cout << count / 2 << "G memory has been allocated" << endl;
        }
    }

    return 0;
}