Malloc inside a function call appears to be getting freed on return?

Question

I think I\'ve got it down to the most basic case:

int main(int argc, char ** argv) {
  int * arr;

  foo(arr);
  printf(\"car[3]=%d\\n\",arr[3]);
  free (arr         


        

Answer 1

You've allocated arr in foo, but that pointers value is stored in the call stack. If you want to do this, do it like this:

void foo( int ** arr) {
    *arr = (int *)malloc( sizeof(int) * 25 );
    (*arr)[3] = 69;
}

And in main, simply pass a pointer to foo (like foo(&arr))