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filter is not described

flush_rewrite_rules_hard filter-hook . WP 3.7.0

Filters whether a "hard" rewrite rule flush should be performed when requested.

A "hard" flush updates .htaccess (Apache) or web.config (IIS).

Usage

add_filter( 'flush_rewrite_rules_hard', 'filter_function_name_7169' );
function filter_function_name_7169( $hard ){
	// filter...

	return $hard;
}
$hard(true/false)
Whether to flush rewrite rules "hard".
Default: true

Where the hook is called

WP_Rewrite::flush_rules()
flush_rewrite_rules_hard
wp-includes/class-wp-rewrite.php 1771
if ( ! $hard || ! apply_filters( 'flush_rewrite_rules_hard', true ) ) {

Where the hook is used (in WP core)

Does not used.