The iOS _MALLOC(size_t size, int type, int flags) function allocates size bytes on the heap. Internally blocks are represented as a length field followed by a data field:

struct _mhead {
size_t mlen;
char dat[0]; }

The mlen field is used by the free() function to determine how much space needs to be freed. In iOS 4.x the _MALLOC function was implemented as follows:

1 void * _MALLOC(size_t size, int type, int flags) {
2 struct _mhead *hdr;
3 size_t memsize = sizeof (*hdr) + size;
4 hdr = (void *)kalloc(memsize); // allocate memory
5 hdr->mlen = memsize;
6 return (hdr->dat);
7 }

In iOS 5.x the following two lines were added after line 3:

int o = memsize < size ? 1 : 0;
if (o) return (NULL);

Why were these lines added in iOS5.x? Briefly describe an attack that may be possible without these lines.

The correct answer to go in the blank would be a) complement.

Answercombo box

(java)3. the answer is  (c): x[2] = 12; if x is an array with three elements, the first element has index 0. the second index has index 1. the third and final element has index 2.4. the answer is (d) for (int y : x) { system.out.println (y) ; }this is an example of syntax  of a "for-each loop."for each element in the integer array x, use y to indicate the current element to do some code with it.the other choice, (c) for (int x : y) { system.out.println (y) ; }. in a for-each loop, the variable to the right of the colon is the array variable; the one to the left is the control variable.choices (a) and (b) have invalid syntax.5. the answer is (a)  int x = {1, 2, 3, 5, 10}; you need to indicate that it is an array using []. without using [], you are trying to assign an array to an integer. you need to use int[] to indicate integer array.so choice (a) has incorrect syntax.