我怎样才能检测是否有输入标准输入等待窗口？ [英] How can I detect if there is input waiting on stdin on windows?

问题描述

我要检测是否存在输入在Windows上的标准输入等待。

我用下面的通用结构在Linux上：

  FD_SET currentSocketSet;
timeval结构电视;
tv.tv_sec = 0;
tv.tv_usec = 0;
INT结果= 1;
而（结果大于0）{
    FD_ZERO（安培; currentSocketSet）;
    FD_SET（STDIN，＆安培; currentSocketSet）;
    结果=选择（STDIN + 1，＆安培; currentSocketSet，NULL，NULL，＆安培;电视）;
    如果（结果== -1）{
        的printf（网络错误 - 选择出错的使用id =％d个\\ n，错误号）;
        返回;
    }否则如果（结果大于0）{
        //...做东西
    }
}
 

请注意：我不想处理类似的kbhit键盘和键盘功能。我想办法做什么我问。我不希望第三方库要么做到这一点，我想一个原生的Windows库调用才能得到答案。

注2：在Windows上高于code不能与Windows错误code 10038试图在了一个操作不是一个套接字，这可能意味着Windows不支持选择的标准输入<。 / p>

解决方案

由于在的 ReadConsoleInput（）文档：

  

一个进程可以在的等功能，以确定当有未读控制台输入。当输入缓冲器不为空，一个控制台输入缓冲器手柄的状态信号

  
  

要确定一个控制台输入缓冲区的未读的输入记录的数量，使用的 GetNumberOfConsoleInputEvents 功能。读取控制台输入缓冲器的输入记录，而不影响的未读的记录数，使用的 PeekConsoleInput 功能。要放弃在控制台的输入缓冲区所有未读的记录，使用 FlushConsoleInputBuffer 功能。

您可以使用 GetStdHandle（） 得到一个句柄STDIN在上述功能的使用。

I want to detect whether or not there is input waiting on stdin in Windows.

I use the following generic structure on Linux:

fd_set currentSocketSet;
struct timeval tv;
tv.tv_sec = 0;
tv.tv_usec = 0;
int result = 1;
while (result > 0){
    FD_ZERO(&currentSocketSet);
    FD_SET(STDIN, &currentSocketSet);
    result = select(STDIN+1, &currentSocketSet, NULL, NULL, &tv);
    if (result == -1){
        printf("Network Error -- select errored with id=%d.\n", errno);
        return;
    } else if (result > 0){
        //...do stuff
    }
}

Note: I do not want to deal with the keyboard and keyboard functions like kbhit. I want a way to do what I asked. I do not want a third party library to do this either, I would like a native Windows library call to get the answer.

Note #2: On windows the above code fails with windows error code 10038 "An operation was attempted on something that is not a socket" which probably means that windows does not support selecting on STDIN.

解决方案

As stated in the ReadConsoleInput() documentation:

A process can specify a console input buffer handle in one of the wait functions to determine when there is unread console input. When the input buffer is not empty, the state of a console input buffer handle is signaled.

To determine the number of unread input records in a console's input buffer, use the GetNumberOfConsoleInputEvents function. To read input records from a console input buffer without affecting the number of unread records, use the PeekConsoleInput function. To discard all unread records in a console's input buffer, use the FlushConsoleInputBuffer function.

You can use GetStdHandle() to get a handle to STDIN for use in the above functions.

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