C 二级指针

#include <iostream>
using namespace std;



void  my_malloc(char **s)    
{    
	char* m=NULL;
	char key[]="zhang"; 
	printf("%d\r\n",s);
	m =(char*)malloc(100);  
	printf("%d\r\n",m);
	
	memcpy(m,key,sizeof(key));
	*s = m;
}    
  


void  main()    
{    
    char  *p=NULL; 
	

	printf("%d\r\n",&p);
    my_malloc(&p);
	printf("%d\r\n",*(&p));
	

	printf("%s",p);


    //do something  
    if(p)
	{
		free(*(&p));
	}
       
}