syntax error in accessing a structure

[jamesbon]

I am writing a small program


#include<stdio.h>
#include<stdlib.h>
struct node {
struct node *left, *right;
int data, color;
} *root;
int index=0;
typedef struct node tree;
void create_tree(int);
int main()
{
int i, j, value;
printf("enter value \n");
scanf("%d", &value);
create_tree(value);
}

void create_tree(int num)
{
tree *temp;
if (index == 0) {
root = (tree *) malloc(sizeof(tree));
root->data = num;
}
if(index>0){
temp=(tree *) malloc(sizeof(tree));
tree->data=num;

}
index++;
}


but I got following syntax error


tree.c:7: warning: built-in function ‘index’ declared as non-function
tree.c: In function ‘create_tree’:
tree.c:27: error: expected identifier or ‘(’ before ‘->’ token

What are these errors and why am I getting the above warnings?

[GeneralZod]

tree->data=num;


=>



temp->data=num;


Edit:

The warning is problem due to a name-clash with this:

http://www.gnu.org/s/libc/manual/html_node/Search-Functions.html#index-index-565

[jamesbon]

Oh thanks
I modified the code and now it gives a new warning


#include<stdio.h>
#include<stdlib.h>
struct node {
struct node *left, *right;
int data, color;
} *root;
int check=0;
typedef struct node tree;
tree * create_tree(int);
int main()
{
int i, j, value;
tree *nv;
printf("enter value \n");
scanf("%d", &value);
nv=create_node(value);
}

tree * create_node(int num)
{
tree *temp;
if (check == 0) {
root = (tree *) malloc(sizeof(tree));
root->data = num;
}
if(check!=0){

temp=(tree *) malloc(sizeof(tree));
temp->data=num;

}
check++;
return temp;
}
the warning is


tree.c: In function ‘main’:
tree.c:16: warning: assignment makes pointer from integer without a cast
tree.c: At top level:
tree.c:19: error: conflicting types for ‘create_node’
tree.c:16: note: previous implicit declaration of ‘create_node’ was here

Why is this warning/error present and how can I overcome it?
I want to have tree as typedef to a pointer to a structure of type node.

[GeneralZod]

You have not declared create_node before you use it on line 16.