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filter is not described

expiration_of_site_transient_(transient) filter-hook . WP 4.4.0

Filters the expiration for a site transient before its value is set.

The dynamic portion of the hook name, $transient, refers to the transient name.

Usage

add_filter( 'expiration_of_site_transient_(transient)', 'filter_function_name_1134', 10, 3 );
function filter_function_name_1134( $expiration, $value, $transient ){
	// filter...

	return $expiration;
}
$expiration(int)
Time until expiration in seconds. Use 0 for no expiration.
$value(mixed)
New value of site transient.
$transient(string)
Transient name.

Where the hook is called

set_site_transient()
expiration_of_site_transient_(transient)
wp-includes/option.php 1765
$expiration = apply_filters( "expiration_of_site_transient_{$transient}", $expiration, $value, $transient );

Where the hook is used (in WP core)

Does not used.