int
pt_insert(struct pt_context *pt, struct tcp_connection *c)
{
struct pt_node *rn = NULL;
u_char key1[KEY_BYTES], key2[KEY_BYTES];
int b;

if (pt->head == NULL)
{
/* make a new head node */
pt->head = pt_new(MIN_KEY_BIT -1, NULL, NULL, c);
if (pt->head == NULL)
{
perror("pt_insert(): malloc(): ");
return (0);
}
else
{
/* increment node counter and return success */
pt->n++;
return (1);
}
}
else
{
memset(key1, NULL, KEY_BYTES);
pt_make_key(key1, c);

switch (pt_search_r(pt->head, key1, &*rn))
{
case 0:
memset(key2, NULL, KEY_BYTES);
pt_make_key(key2, rn->con);

/* find the first differing bit, and its value */
rn->bit = diff_bit(key1, key2, &b);

...2... if (((b ? rn->r : rn->l) == pt_new(MIN_KEY_BIT - 1, NULL, NULL, c)) == NULL)
{
return (0);
}

..3.. if (((b ? rn->l : rn->r) == pt_new(MIN_KEY_BIT - 1, NULL, NULL, rn->con)) == NULL)
{
free(b ? rn->r : rn->l);
return (0);
}
rn->con = NULL;

pt->n += 2;
return (1);
case 1:
return (2);
}
}
return (0);
}

these three red line i am getting warning like this.
1. warning: passing argument 3 of ‘pt_search_r’ from incompatible pointer type
2.comparison between pointer and integer
3.comparison between pointer and integer
how can i solve this problem?

Well, did you look at it:

What the heck is &*rn?
You've got to be kidding, right? If the argument takes a pointer to pointer to pt_node and rn is a pointer to pt_node, then wouldn't you use &rn as the argument? I mean, really...
The message is about the last NULL (The arguments to the function take pointers, so the first twoNULLs are OK.)
NULL is a pointer, not an integer. (Converting NULL to an integer may give a value of zero, but if you want to see if the value of an expression is equal zero, use zero, not NULL. Unlike the first message, I think that the second and third are not fatal, but the idea is to get rid of the warnings by using the proper notation.


Regards,

Dave

Footnote: Since this is a continuation of your previous question (I assume it is the same program), the proper protocol is to continue on the same thread, not start at new one. Not a big deal, but think about it next time.

Many thanks for feedback.
Nasim