wp_specialchars( string $string, string $quote_style = ENT_NOQUOTES, false|string $charset = false, false $double_encode = false )

Source

File: wp-includes/deprecated.php

function wp_specialchars( $string, $quote_style = ENT_NOQUOTES, $charset = false, $double_encode = false ) {
	_deprecated_function( __FUNCTION__, '2.8.0', 'esc_html()' );
	if ( func_num_args() > 1 ) { // Maintain back-compat for people passing additional arguments.
		return _wp_specialchars( $string, $quote_style, $charset, $double_encode );
	} else {
		return esc_html( $string );
	}
}