nonblocking read from stdin

Question

I expect ReadConsoleW() to return after reading a specific number of bytes. But it doesn't return.

How can I make ReadConsoleW() return as soon as it finished reading the number of bytes specified?

The code I tried is here:

#include <stdio.h>
#include <Windows.h>


int main()
{
    //something is being written to stdin.
    Sleep(2000);
    int b;
    int r;
    //read 3 wide character
    ReadConsoleW(GetStdHandle(STD_INPUT_HANDLE), &b, 3*sizeof(TCHAR), (LPDWORD)&r, NULL);
    //problem: no returns until enter pressed
    putc(b,stdout);
    while(1)
    {};
}

Answer 1

Use SetConsoleMode to turn off ENABLE_LINE_INPUT flag. No line editing will be available, but it won't wait until the Enter is pressed.

Note that you can't read three WCHARs into an int.