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filter is not described

http_request_version filter-hook . WP 2.7.0

Filters the version of the HTTP protocol used in a request.


add_filter( 'http_request_version', 'filter_function_name_1999' );
function filter_function_name_1999( $version ){
	// filter...

	return $version;
Version of HTTP used. Accepts '1.0' and '1.1'.
Default: '1.0'

Where the hook is called

wp-includes/class-http.php 175
'httpversion' => apply_filters( 'http_request_version', '1.0' ),

Where the hook is used (in WP core)

Does not used.