.htaccess 編碼 - BBS

.htaccess 在產生密碼檔(.passwd)時 一般是下指令

#htpasswd .passwd username
New password:
Re-type new password:

欲寫一個php程式 更改.htaccess 的密碼檔 (.passwd)

好像不是MD5 請問他是怎樣編碼的~~
http://www.euronet.nl/~arnow/htpasswd/
---附上簡短程式---
<?
$name=$_POST["Name"];
$passwd=$_POST["Password"];
$passwd2=$_POST["Password2"];
if ($passwd == $passwd2)
{
print "姓名: ".$name."<br>";
print "密碼: ".$passwd."<br>";
$enc_passwd = md5($passwd); //這一行
$content = "$name:$enc_passwd";
$filename = ".passwd";
if (!file_exists($filename)) {
$file = fopen ($filename,"w");
fclose ($file);
}
$file = fopen ($filename,"w");
fputs ($file , $content);
fclose ($file);
}
else {
print "密碼不符合 請從新輸入";
}
?>

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