c++ - How can I detect if there is input waiting on stdin on windows?

Question

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.
", 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.

Answer 1

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.