#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
#include <sys/resource.h>  
#include <errno.h>  
#include <iostream>
// 用於記憶體不足的情況下程式退出
static char *reservedMemoryForExit;

void outOfMemoryHandler()
{
	static bool isInHandler = false;
	if (isInHandler) return;
	isInHandler = true;

	// 釋放保留記憶體，以免程式退出過程中再次出現記憶體不足
	delete[] reservedMemoryForExit;
	reservedMemoryForExit = NULL;
	printf("Memory Not Enough exit");
	abort();
}


void initNewOperHandler()
{
	const int RESERVED_MEM_SIZE = 1024 * 1024 * 2; // 2M
	std::set_new_handler(outOfMemoryHandler);
	// 用於記憶體不足的情況下程式退出
	reservedMemoryForExit = new char[RESERVED_MEM_SIZE];
}


int main(void)  
{  
    int nMemoryLimit = 1024 * 1024 * 20;//5M  
  
    struct rlimit64 memoryL;  
  
  	
  
    getrlimit64(RLIMIT_AS, &memoryL);  
    printf("before set mem:%lu,%lu\r\n", (unsigned long)memoryL.rlim_cur, (unsigned long)memoryL.rlim_max);  
  
    memoryL.rlim_cur = nMemoryLimit;  
    memoryL.rlim_max = nMemoryLimit;  
    setrlimit64(RLIMIT_AS ,&memoryL);  
  
    getrlimit64(RLIMIT_AS, &memoryL);  
    printf("after set mem:%lu,%lu\r\n", (unsigned long)memoryL.rlim_cur, (unsigned long)memoryL.rlim_max);  
  
  	initNewOperHandler();
  	
    int i = 0;  
    while(1)  
    {  
        i++;  
        //當程序記憶體達到最大值時，malloc calloc返回NULL,記錄錯誤errno=ENOMEM  
        errno  = 0;  
        char *psString = (char *)calloc(1, 1024);  
        if(NULL == psString)  
        {  
            printf("errno=%d, ENOMEM=%d\r\n", errno, ENOMEM);  
        }  
        else  
        {  
            printf("success, %d\r\n", i);  
        }  
    }  
    return 0;  
}