C++ 强制 std::cout 刷新（打印到屏幕）
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/22026751/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
c++ force std::cout flush (print to screen)
提问by synaptik
I have code such as the following:
我有如下代码：
std::cout << "Beginning computations..."; // output 1
computations();
std::cout << " done!\n"; // output 2
The problem, however, is that often output #1 and output #2 appear (virtually) simultaneously. That is, often output #1 does not get printed to the screen until after computations()returns. Since the entire purpose of output #1 is to indicate that something is going on in the background (and thus to encourage patience from the user), this problem is not good.
然而，问题是输出#1 和输出#2 经常（几乎）同时出现。也就是说，在computations()返回之前，输出 #1 通常不会打印到屏幕上。由于输出 #1 的全部目的是表明后台正在发生某些事情（从而鼓励用户的耐心），因此这个问题并不好。
Is there any way to force the std::coutbuffer to get printed before the computations()call? Alternatively, is there some other way (using something other than std::cout) to print to standard out that would fix this problem?
有什么方法可以强制std::cout在computations()调用之前打印缓冲区？或者，是否有其他方法（使用 以外的其他方法std::cout）打印到标准输出可以解决此问题？
回答by Joseph Mansfield
Just insert std::flush:
只需插入std::flush：
std::cout << "Beginning computations..." << std::flush;
Also note that inserting std::endlwill also flush after writing a newline.
另请注意，std::endl在写入换行符后插入也会刷新。
回答by user1810087
In addition to Joseph Mansfield answer, std::endldoes the flush too (besides a new line).
除了 Joseph Mansfield 的回答之外，std::endl也进行了冲洗（除了换行）。
Inserts a endline character into the output sequence os and flushes it as if by calling os.put(os.widen('\n')) followed by os.flush().
将结束符插入到输出序列 os 中并刷新它，就像调用 os.put(os.widen('\n')) 后跟 os.flush() 一样。
