_links_add_base() │ WP 2.7.0

Callback to add a base URL to relative links in passed content.

Internal function — this function is designed to be used by the kernel itself. It is not recommended to use this function in your code.

No Hooks.

Returns

String. The processed link.

Usage

_links_add_base( $m );
$m(string) (required)
The matched link.

Notes

  • Global. String. $_links_add_base

Changelog

Since 2.7.0 Introduced.

_links_add_base() code WP 6.8.3

wp-includes/formatting.php 
function _links_add_base( $m ) {
	global $_links_add_base;
	// 1 = attribute name  2 = quotation mark  3 = URL.
	return $m[1] . '=' . $m[2] .
		( preg_match( '#^(\w{1,20}):#', $m[3], $protocol ) && in_array( $protocol[1], wp_allowed_protocols(), true ) ?
			$m[3] :
			WP_Http::make_absolute_url( $m[3], $_links_add_base )
		)
		. $m[2];
}