Description

The following code:

<?php
var_dump(mb_strpos("AあいうえおBBcC", "?", 0, "ISO-2022-JP"));
var_dump(mb_stripos("AあいうえおBBcC", "?", 0, "ISO-2022-JP"));
var_dump(mb_strpos("AあいうえおBBcC", "?", 0, "SJIS"));
var_dump(mb_stripos("AあいうえおBBcC", "?", 0, "SJIS"));

Resulted in this output:

int(1)
int(5)
int(1)
int(5)

But I expected this output instead:

bool(false)
bool(false)
bool(false)
bool(false)

note: mb_stripos is affect mb_substitute_character, but mb_strpos is not affect it is (3v4l: https://3v4l.org/872nB )

PHP Version

PHP 8.1.x

Operating System

Ubuntu 20.04 on WSL2