function wp_get_nocache_headers() {
$headers = array(
'Expires' => 'Wed, 11 Jan 1984 05:00:00 GMT',
- 'Last-Modified' => '',
'Cache-Control' => 'no-cache, must-revalidate, max-age=0',
'Pragma' => 'no-cache',
);
if ( function_exists('apply_filters') ) {
$headers = (array) apply_filters('nocache_headers', $headers);
}
+ $headers['Last-Modified'] = false;
return $headers;
}
*/
function nocache_headers() {
$headers = wp_get_nocache_headers();
+
+ unset( $headers['Last-Modified'] );
+
+ // In PHP 5.3+, make sure we are not sending a Last-Modified header.
+ if ( function_exists( 'header_remove' ) ) {
+ @header_remove( 'Last-Modified' );
+ } else {
+ // In PHP 5.2, send an empty Last-Modified header, but only as a
+ // last resort to override a header already sent. #WP23021
+ foreach ( headers_list() as $header ) {
+ if ( 0 === stripos( $header, 'Last-Modified' ) ) {
+ $headers['Last-Modified'] = '';
+ break;
+ }
+ }
+ }
+
foreach( $headers as $name => $field_value )
@header("{$name}: {$field_value}");
- if ( empty( $headers['Last-Modified'] ) && function_exists( 'header_remove' ) )
- @header_remove( 'Last-Modified' );
}
/**