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function is not described

update_network_cache() WP 4.6.0

Updates the network cache of given networks.

Will add the networks in $networks to the cache. If network ID already exists in the network cache then it will not be updated. The network is added to the cache using the network group with the key using the ID of the networks.

No Hooks.

Return

Nothing (null).

Usage

update_network_cache( $networks );
$networks(array) (required)
Array of network row objects.

Code of update network cache: wp-includes/ms-network.php VER 5.1.1

<?php
function update_network_cache( $networks ) {
	foreach ( (array) $networks as $network ) {
		wp_cache_add( $network->id, $network, 'networks' );
	}
}