From man realloc:The realloc() function returns a pointer to the newly allocated memory, which is suitably aligned for any kind of variable and may be different from ptr, or NULL if the request fails.
So in this code snippet:
ptr = (int *)…
Question says it all but here is an example:
typedef struct mutable_t{
int count, max;
void **data;
} mutable_t;
void pushMutable(mutable_t *m, void *object)
{
if(m->count == m->max){
m->max *= 2;
m->data =…
I have a few related questions about managing aligned memory blocks. Cross-platform answers would be ideal. However, as I'm pretty sure a cross-platform solution does not exist, I'm mainly interested in Windows and Linux and to a (much) lesser…
There exist several aligned versions of the venerable malloc(), e.g.:
#include
int posix_memalign(void **memptr, size_t alignment, size_t size);
void *aligned_alloc(size_t alignment, size_t size);
#include
void…
The realloc reference says:
The function may move the memory block
to a new location, in which case the
new location is returned.
Does it mean that if I do this:
void foo() {
void* ptr = malloc( 1024 );
unsigned char* cptr =…
std::realloc is dangerous in c++ if the malloc'd memory contains non-pod types. It seems the only problem is that std::realloc wont call the type destructors if it cannot grow the memory in situ.
A trivial work around would be a try_realloc…
Can anyone summarize what is the correct usage of realloc()?
What do you do when realloc() fails?
From what I have seen so far, it seems that if realloc() fails, you have to free() old pointer. Is that true?
Here is an example:
1. char *ptr =…
Everyone knows that:
realloc resizes an existing block of memory or copies it to a larger block.
calloc ensures the memory is zeroed out and guards against arithmetic overflows and is generally geared toward large arrays.
Why doesn't the C…
Some time ago a friend of mine told me not to use realloc because it's unsafe, but he couldn't tell me why, so I made some research on the subject and the nearest references to my doubt were:
First
Second
I want to know if I can continue to use…
so I have a piece of memory allocated with malloc() and changed later with realloc().
At some point in my code I want to empty it, by this I mean essentially give it memory of 0. Something which would intuitively be done with realloc(pointer,0). I…
I have cloned a large repo and got an error (after several attempts)
Clone succeeded, but checkout failed
When trying to fix this with
git checkout -f HEAD
an error comes back
Fatal: Out of memory, realloc failed2
I've already set some memory…
While there are lots of different sophisticated implementations of malloc / free for C/C++, I'm looking for a really simple and (especially) small one that works on a fixed-size buffer and supports realloc. Thread-safety etc. are not needed and my…
If do the next:
int* array = malloc(10 * sizeof(int));
and them I use realloc:
array = realloc(array, 5 * sizeof(int));
On the second line (and only it), can it return NULL?
realloc is used to reallocate the memory dynamically.
Suppose I have allocated 7 bytes using the malloc function and now I want to extend it to 30 bytes.
What will happen in the background if there is no sequential (continously in a single row)…
