Problem with select() on console

[Christopher Faylor]

On Thu, Jul 15, 2010 at 01:44:19AM +0100, Cliff Hones wrote:
>When select() is used to test for input availability on the standard
>cygwin console in normal (cooked) mode, it indicates input is available
>as soon as any key is pressed.  However, a call to read(0,...)
>will (correctly) block until a terminating RETURN is entered.
>
>select() should only indicate input is available when a call
>to read would *not* block - ie when a read call will immediately
>return at least one character or an error such as EOF.
>
>The behaviour of the following test case illustrates this.  When run
>in a console window typing a single key causes the program to wait
>for the whole line.  When run under mintty or on Linux the
>select() calls will continue to return no input until RETURN is
>entered.

Since, AFAIK, Windows has no way to do this, I don't see how it could be
done easily.  You could, I guess, pull characters into a buffer until a
newline was found but that would be pretty error-prone and any use of
select() would potentially invalidate console i/o for subprocesses.

So, I don't see this changing anytime soon.

cgf

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