How to do non-blocked I/O?

[Peter Steele]

I want to modify our system startup scripts to ask a question like

    Okay to bring up databases (y/n)?

and if there is no reply within, say 5 seconds, assume "y". Can
I do this from sh or csh or do I have to write a C program to
do the I/O? If a C program is required, can someone point me
to the best reference on how to do non-blocking I/O? Thanks.
-- 
Peter Steele  Postmaster  peter.steele at acadiau.ca   Tel: 902-542-2201
Software Analyst, Acadia University, Wolfville, NS  Fax: 902-542-7224