Problem using void pointer as a function argument

Posted by Nazgulled on Stack Overflow See other posts from Stack Overflow or by Nazgulled
Published on 2010-04-07T00:18:30Z Indexed on 2010/04/07 0:23 UTC
Read the original article Hit count: 643

Filed under:

pointers

|

void-pointers

|

function

|

argument-passing

|

c

Hi,

I can't understand this result...

The code:

void foo(void * key, size_t key_sz) {
    HashItem *item = malloc(sizeof(HashItem));

    printf("[%d]\n", (int)key);

    ...

    item->key = malloc(key_sz);
    memcpy(item->key, key, key_sz);
}

void bar(int num) {
    foo(&num, sizeof(int));
}

And I do this call: bar(900011009);

But the printf() output is:

[-1074593956]

I really need key to be a void pointer, how can I fix this?

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