Description:
------------
Windows system, run a php file with chinese character in PHP CLI mode, it return s unexpected value

PHP 5.6.40 is ok
PHP 7.0.33 is ok
PHP >= 7.1.33 is bad

Test script:
---------------
<?php

while (1) {
	$s = fgets(STDIN);
	echo var_dump($s);
	echo bin2hex($s);
	echo "\r\n";
}


Expected result:
----------------
aaa
string(5) "aaa
"
6161610d0a
你好
string(6) "你好
"
c4e3bac30d0a


Actual result:
--------------
aaa
string(5) "aaa
"
6161610d0a
你好
string(4) "\000\000
"
00000d0a