%WAITINPUT Prompt for user input, but no longer than t seconds.
% output = WAITINPUT('Input something',t) gives the user the prompt in the
% text string and then waits for input from the keyboard by t seconds.
% R is the result. When user not specified s argument R will be a double,
% or if argument s i s eqal to 's', R will be a char. For other s
% argument function return an error.
% Function works only with alphanumeric characters.
% waitinput('what is your name? ',10,'s')
% This function is inspired by Matlab INPUT function and GetKeyWait by
% Jos (10584) from File Exchange:
% See also INPUT, KEYBOARD.
% Copyright 2010 Grzegorz Knor