If a maxtime is specified (in seconds) then the program loops. If maxtime < 500 then no messages are transmitted and the program just exits. In addition it transmits the `dome center' message before each sleep. If the dome closes at any time the program dies with a non-zero exit code.
noslit - turns off the slit keepopen message.
nodome - turns off the dome centering message.
keepopen will return an error if the sun is higher than 10 degrees above the horizon.
Error messages will not be printed unless the `verbose' flag is used.