大约有 42,000 项符合查询结果（耗时：0.0305秒） [XML]
What exactly is a reentrant function?
...e, however the only problem is you forgot to say exactly where the lock is allocated.
– Yttrill
Dec 10 '10 at 4:58
3
...
How are virtual functions and vtable implemented?
...(which it usually isn't) (ISO/IEC 14882:2003 10.4-2). In practice it does allocate a slot in the vtable for the function but does not assign an address to it. This leaves the vtable incomplete which requires the derived classes to implement the function and complete the vtable. Some implementations...
How to detect when an Android app goes to the background and come back to the foreground
...rocess had been showing a user interface, and is no longer doing so. Large allocations with the UI should be released at this point to allow memory to be better managed.
Of course, you should implement this to actually do what it says (purge memory that hasn't been used in certain time, clear some...
Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...though threads are relatively easy to create and use, the operating system allocates a significant amount of time and other resources to manage them."
CreateThread documentation on MSDN says "However, your application will have better performance if you create one thread per processor and build queu...
What are the differences between the threading and multiprocessing modules?
...faster to create and manage than processes (because the OS doesn't need to allocate a whole new virtual memory area), and inter-thread communication is usually faster than inter-process communication. But threads are harder to program. Threads can interfere with one another, and can write to each ot...
Fill remaining vertical space with CSS using display:flex
...n which case they would get equal space after the fixed container space is allocated.
Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec quam felis, ult...
Which kind of pointer do I use when?
... managing memory.
The costs:
If you have a custom deleter (e.g. you use allocation pools) then this will incur overhead per pointer that may be easily avoided by manual deletion.
std::shared_ptr has the overhead of a reference count increment on copy, plus a decrement on destruction followed by a...
What is the purpose of setting a key in data.table?
...dix sorting) and memory efficient (only one extra column of type double is allocated).
When is setkey() required?
For grouping operations, setkey() was never an absolute requirement. That is, we can perform a cold-by or adhoc-by.
## "cold" by
require(data.table)
DT <- data.table(x=rep(1:5, ea...
A complete solution to LOCALLY validate an in-app receipts and bundle receipts on iOS 7
...ceipt:
{
RMAppReceiptIAP *purchase = [[RMAppReceiptIAP alloc] initWithASN1Data:data];
[purchases addObject:purchase];
break;
}
case RMAppReceiptASN1TypeOriginalAppVersion:
_originalAppVersion = RMASN1ReadUTF8String(&s, lengt...
Ternary operator is twice as slow as an if-else block?
...erator. it's usage in this case just happens to cause a different register allocation. In a different case, it might be faster than if/else, as I tried to explain in my answer.
– Eren Ersönmez
Jun 27 '13 at 12:41
...