WordPress at a glance
function is not described

wp_get_server_protocol() WP 4.4.0

Return the HTTP protocol sent by the server.

No Hooks.

Return

String. The HTTP protocol.0.

Usage

wp_get_server_protocol();

Changelog

Since 4.4.0 Introduced.

Code of wp_get_server_protocol() WP 5.7

<?php
function wp_get_server_protocol() {
	$protocol = isset( $_SERVER['SERVER_PROTOCOL'] ) ? $_SERVER['SERVER_PROTOCOL'] : '';
	if ( ! in_array( $protocol, array( 'HTTP/1.1', 'HTTP/2', 'HTTP/2.0' ), true ) ) {
		$protocol = 'HTTP/1.0';
	}
	return $protocol;
}