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How much is the overhead of smart pointers compared to normal pointers in C++?
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shared_ptr has a significant overhead for creation because of it's memory allocation for the control block (which keeps the ref counter and a pointer list to all weak references). It has also a huge memory overhead because of this and the fact that std::shared_ptr is always a 2 pointer tuple (one t...
MySQL maximum memory usage
...5-8 so called important settings. First off, not all of them matter - e.g. allocating a lot of resources to InnoDB and not using InnoDB doesn't make a lot of sense because those resources are wasted.
Or - a lot of people suggest to up the max_connection variable -- well, little do they know it also...
Can I use Objective-C blocks as properties?
... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC)
– Robert
Mar 31 '13 at 21:58
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What does string::npos mean in this code?
...rison with string::npos might not work.
size_type, which is defined by the allocator of the string, must be an unsigned
integral type. The default allocator, allocator, uses type size_t as size_type. Because -1 is
converted into an unsigned integral type, npos is the maximum unsigned value of its ty...
C compile error: “Variable-sized object may not be initialized”
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I can use for this purpose malloc as well, what about the second question, I wrote it after Pavel's reply
– helloWorld
Jun 21 '10 at 8:10
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Count the items from a IEnumerable without iterating?
... edited Sep 29 '16 at 17:18
c0d3b34n
47966 silver badges1313 bronze badges
answered Oct 4 '08 at 3:49
Rober...
Container View Controller Examples [closed]
...tion
self.navigationItem.rightBarButtonItem =
[[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemEdit
target:self
action:@selector(button:)]
...
What is the difference between mutex and critical section?
...n
the critical section structure holds room for a mutex. It is initially unallocated
if there is contention between threads for a critical section, the mutex will be allocated and used. The performance of the critical section will degrade to that of the mutex
if you anticipate high contention, you c...
Does free(ptr) where ptr is NULL corrupt memory?
...cription
The free function causes the space pointed to by ptr to be deallocated, that is, made
available for further allocation. If ptr is a null pointer, no action occurs.
See ISO-IEC 9899.
That being said, when looking at different codebases in the wild, you'll notice people sometimes d...
How do you implement a class in C? [closed]
...se C (no C++ or object oriented compilers) and I don't have dynamic memory allocation, what are some techniques I can use to implement a class, or a good approximation of a class? Is it always a good idea to isolate the "class" to a separate file? Assume that we can preallocate the memory by assumin...