[CentOS] is there a utility to tell if the monitor is on or offin CentOS?

Sir,

Thanks for the suggestion. However I did a xset -q | grep Monitor and it 
says "On".
I then turned off the monitor did a cursor up to execute the last 
command hit enter,
turned the monitor back on and it still said "On". I then unplugged the 
monitor,
cursor up to execute last command hit enter, turned back on the monitor 
and it still
said "On".

Do you have another suggestion? Thank you.

Jerry