DOCUMENTATION 1 (Current Proposal)

PRE_TEMPLATE HOOK
This hook action is called just before the output html is put together and is a prerequisite if you wish to use the POST_TEMPLATE Hook to modify output later.

To run it, initialise it in your plugin as follows "plugin_add_hook('PRE_TEMPLATE',  'plugin_x_capture_output');"
Then, define the function with your code as follows...
function plugin_x_capture_output($t) {
	//YOUR CODE GOES HERE IF REQUIRED
	ob_start();
	return $t;
}

If you simply want to run some code before the output html is put together but do not wish to use the POST_TEMPLATE Hook to modify output later, define the function as follows ....
function plugin_x_capture_output($t) {
	//YOUR CODE GOES HERE
	return $t;
}
P.S: Try not to change the value of "$t", as we need it intact to use later on in the process.

POST_TEMPLATE HOOK
This hook action is called just before the output html is sent to the browser and requires the PRE_TEMPLATE Hook.

To run it, initialise it in your plugin as follows "plugin_add_hook('POST_TEMPLATE', 'plugin_x_process_output');"

Then, define the function with your code as follows...
function plugin_x_process_output() {
	$template_output = ob_get_contents();
	ob_end_clean();
    $template_output = YOUR CODE TO MODIFY OUTPUT
	echo $template_output;
}

DOCUMENTATION 2 (Revised Proposal)

PRE_TEMPLATE HOOK
This hook action is called just before the output html is put together and is a prerequisite if you wish to use the POST_TEMPLATE Hook to modify output later.

To run it, initialise it in your plugin as follows "plugin_add_hook('PRE_TEMPLATE',  'plugin_x_capture_output');"
Then, define the function with your code as follows...
function plugin_x_capture_output() {
	//YOUR CODE GOES HERE IF REQUIRED
	return null;
}

POST_TEMPLATE HOOK
This hook action is called just before the output html is sent to the browser and requires the PRE_TEMPLATE Hook.

To run it, initialise it in your plugin as follows "plugin_add_hook('POST_TEMPLATE', 'plugin_x_process_output');"
Then, define the function with your code as follows...
function plugin_x_process_output($input_html) {
    $output_html = YOUR CODE TO MODIFY $input_html
	return $output_html;
}