How can I read keyboard without stopping

[Harris Reavin]

	I would like to know if it is possible to get input data from the
keyboard while my program is constantly looping and displaying output to
the screen. The input comes from a call to "popen()".
I am using C, curses, and BSD4.2 on a VAX-780. I have only been
able to enter input if the display stops for "getch()". This is not acceptable
because I want the display to be continuous unless I am going to change one
of the parameters.  For my PC I have Aspen Curses which has a "nodelay()" 
function that indicates the presence of characters in the keyboard buffer. 
Is there an some way to do this under UNIX?
-- 
Harris Reavin
ISN, Crystal City, VA, 703-979-8900
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