Registers the function named by
function to be executed when script processing is
complete.
Multiple calls to
register_shutdown_function() can be made, and each will
be called in the same order as they were registered. If you
call
exit() within one registered shutdown function,
processing will stop completely and no other registered
shutdown functions will be called.
The registered shutdown functions are called after the
request has been completed (including sending any output
buffers), so it is not possible to send output to the browser
using
echo() or print(), or retrieve the contents of any
output buffers using
ob_get_contents().