WordPress at a glance
action is not described

deprecated_function_run action-hook . WP 2.5.0

Fires when a deprecated function is called.

Usage

add_action( 'deprecated_function_run', 'action_function_name_4876', 10, 3 );
function action_function_name_4876( $function, $replacement, $version ){
	// action...
}
$function(string)
The function that was called.
$replacement(string)
The function that should have been called.
$version(string)
The version of WordPress that deprecated the function.

Changelog

Since 2.5.0 Introduced.

Where the hook is called

_deprecated_function()
deprecated_function_run
wp-includes/functions.php 4839
do_action( 'deprecated_function_run', $function, $replacement, $version );

Where in WP core the hook is used WordPress

wp-includes/functions.php 198
add_action( 'deprecated_function_run', 'rest_handle_deprecated_function', 10, 3 );