//Hide content
add_shortcode( 'member', 'member_check_shortcode' );

function member_check_shortcode( $atts, $content = null ) {
	 if ( is_user_logged_in() && !is_null( $content ) && !is_feed() )
		return $content;
	return '';
}<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /home/dmoviezc/public_html/wp-content/themes/thesis_1821/custom/custom_functions.php:31) in <b>/home/dmoviezc/public_html/wp-includes/pluggable.php</b> on line <b>866</b><br />