Re: std::cin and disabling canonical line processing (buffering)

Tom,

Well I tried this and it almost works. Unfortunately, it looks like
newline/carriage-return filtering is still happening. I can get any character
immediately except for \r or \n. I cannot seem to get a newline (^J) no
matter what, and 2 consecutive \r chars are needed to get one response out of
std::cin.get(c)

I've looked throughout the console function documentation and I cannot find
any reference to turning this behaviour off.

Sorry to be such a pain, but I could still use another clue.

Thanks.

-- Harold


"Tom Widmer [VC++ MVP]" wrote:

> Harold Bamford wrote:
> > I would like to read from cin one character at a time (eg, cin.get(thisChar)
> > or the like) and not have to wait for the user to enter a carriage return.
> >
> > On Unix or Cygwin, I would use tcgetattr/tcsetattr to turn off buffering and
> > echoing on file descriptor 0 (STDIN) but this doesn't seem to be available in
> > VC++ 7.1
> >
> > What's the trick?
>
> You could try something along these lines:
>
> #include <windows.h>
> #include <iostream>
>
> int main()
> {
> HANDLE inputHandle = GetStdHandle(STD_INPUT_HANDLE);
> BOOL b = SetConsoleMode(inputHandle, 0);
>
> char c;
> while(std::cin.get(c))
> {
> if (c == 'x')
> break;
> std::cout << c << " typed" << std::endl;
> }
> }
>
> Also, look at the rest of the Console functions, which you might prefer
> to deal with directly.
>
> Tom
>
.

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