大约有 42,000 项符合查询结果（耗时：0.0498秒） [XML]
How expensive is RTTI?
... reasons. However, there are good reasons to use RTTI (mainly because of boost::any). That in mind, it's useful to know its actual resource usage in common implementations.
I recently did a bunch of research into RTTI in GCC.
tl;dr: RTTI in GCC uses negligible space and typeid(a) == typeid(b) is v...
Are Exceptions in C++ really slow
...n model used today for exceptions (Itanium ABI, VC++ 64 bits) is the Zero-Cost model exceptions.
The idea is that instead of losing time by setting up a guard and explicitly checking for the presence of exceptions everywhere, the compiler generates a side table that maps any point that may throw an...
Is it better to use std::memcpy() or std::copy() in terms to performance?
...o go against the general wisdom here that std::copy will have a slight, almost imperceptible performance loss. I just did a test and found that to be untrue: I did notice a performance difference. However, the winner was std::copy.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings us...
What do 'statically linked' and 'dynamically linked' mean?
...
There are (in most cases, discounting interpreted code) two stages in getting from source code (what you write) to executable code (what you run).
The first is compilation which turns source code into object modules.
The second, linking, ...
Auto-fit TextView for Android
... + " text:" + text + " maxLines:" + maxLines);
}
});
}
I am posting code here at per android developer's request:
Final effect:
Sample Layout file:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height...
Timer function to provide time in nano seconds using C++
...
What others have posted about running the function repeatedly in a loop is correct.
For Linux (and BSD) you want to use clock_gettime().
#include <sys/time.h>
int main()
{
timespec ts;
// clock_gettime(CLOCK_MONOTONIC, &ts);...
RabbitMQ and relationship between channel and connection
...prefer
using a Channel per thread instead of sharing the same Channel across
multiple threads.
There is no direct relation between Channel and Queue. A Channel is used to send AMQP commands to the broker. This can be the creation of a queue or similar, but these concepts are not tied together....
Why do people say there is modulo bias when using a random number generator?
...asked a lot but never seen a true concrete answer to it. So I am going to post one here which will hopefully help people understand why exactly there is "modulo bias" when using a random number generator, like rand() in C++.
...
How to use the same C++ code for Android and iOS?
Android with NDK has support to C/C++ code and iOS with Objective-C++ has support too, so how can I write applications with native C/C++ code shared between Android and iOS?
...
How does libuv compare to Boost/ASIO?
...
Scope
Boost.Asio is a C++ library that started with a focus on networking, but its asynchronous I/O capabilities have been extended to other resources. Additionally, with Boost.Asio being part of the Boost libraries, its scope is sl...