Why this doesn't work ?

Question

int ***p;

**p=malloc(sizeof(int));

***p=12;

printf("%d",***p);

Answer 1

http://www.howstuffworks.com/c.htm/print...

Answer 2

This leads to  Segmentation fault

Answer 3

Yikes!

int ***p is a pointer to a pointer to a pointer to an int.  However, it isn't ever set to point at a pointer to a pointer to an int.

There isn't a pointer to a pointer to an int for it to point at.  And even if there was (a pointer to a pointer to an int), there isn't a pointer to a int for that to point at. But you do actually malloc an int. Confused?

You would need to do this -

int *p;

int **pp = &p;

int ***ppp = &pp;

*p = malloc (sizeof (int));

***ppp = 12;

printf("%d", *p);

if you did -

printf ("%d", ***ppp);

that should work (I think). You can also do -

printf ("%d", *pp);

printf ("%d", *ppp);

These would print the address of p, and pp respectively.  None of this is a particularly good idea.