(PHP 3 >= 3.0.4, PHP 4, PHP 5)
Register a function for execution on shutdown
( callback function [, mixed parameter [, mixed ...]] )
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.
In PHP 4.0.6 and earlier under Apache,
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().
Since PHP 4.1, the shutdown functions are called as the part of the
request so that it's possible to send the output from them. There is
currently no way to process the data with output buffering functions in
the shutdown function.
Shutdown function is called after closing all opened output buffers thus,
for example, its output will not be compressed if zlib.output_compression is
As of PHP 4, it is possible to pass parameters to the shutdown function by
passing additional parameters to
Typically undefined functions cause fatal errors in PHP, but when the
function called with
register_shutdown_function() is undefined, an error
of level E_WARNING is generated instead. Also,
for reasons internal to PHP, this error will refer to
Unknown at line #0.
Working directory of the script can change inside the shutdown function
under some web servers, e.g. Apache.
Shutdown function is called during the script shutdown so headers are
always already sent.
See also auto_append_file,
exit(), and the section on