I had been trying to use a pointer to pointer in a function,but is seems that I am not doing the memory allocation correctly... My code is:

#include<stdio.h>
#include<math.h>
#include<ctype.h>
#include<stdlib.h>
#include<string.h>


struct list{
       int data;
       struct list *next;
       };
void abc (struct list **l,struct list **l2)
{
     *l2=NULL;
     l2=(struct list**)malloc( sizeof(struct list*));
     (*l)->data=12;
     printf("%d",(*l)->data);
     (*l2)->next=*l2;
     }
     int main()
     {
     struct list *l,*l2;
     abc(&l,&l2);
     system("pause");
     return(0);
     }
 This code compiles,but I cannot run thw program..I get a segmentation fault..What should I do?Any help would be appreciated!