Re: Keyboard input Buffer

[Rick Stevens <rstevens vitalstream com>]

karlp ourldsfamily com wrote:
> In other languages, I can read the keyboard buffer and test for input. Is
> there any command/sh function that will allow for such behavior from
> within a shell script?
>
> I'm envisioning something like:
>
> for i in `ls /dev/tty*`
> do
> something or other
> KEYIN=`check keyboard buffer prg`
>  if [ "$KEYIN" ! '' ] ; then
>    :
>  else
>    do something else
>  fi

You can't "peek" at the keyboard buffer without reading it in bash.
However, you could:

for i in `ls /dev/tty`; do
    something
    read -t 1 TEST
    if [ "foo$TEST" = "foo" ]; then
	nothing was typed in in the last second
    else
	something was typed in, but it's in $TEST now, not the buffer
    fi
done

The value after the "-t" in the read command sets the timeout in
seconds.  You'll be responsible for putting the buffer back together
if you need the data later.
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- Rick Stevens, Senior Systems Engineer     rstevens vitalstream com -
- VitalStream, Inc.                       http://www.vitalstream.com -
-                                                                    -
- Linux is like a wigwam...no windows, no gates...and apache inside! -
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