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Re: Completely stumped (still)

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Christoph Michael Becker wrote:

> Thomas 'PointedEars' Lahn wrote:
>> Christoph Michael Becker wrote:
>>> Thomas 'PointedEars' Lahn wrote:
>>>> Christoph Michael Becker wrote:
>>>>> I'm still confused that it seems that register_globals makes the
>>>>> respective global variables *references* to the session variables.
>>>>
>>>> Or both of them are references to the same array element.  Whatever the
>>>> implementation, it is the case that they yield the same value then, and
>>>> it is – if I may say so – a *logical* consequence of how
>>>> register_globals is supposed to work.
>>>
>>> However, GPC parameters are *copied* to the respective global variables.
>> 
>> How did you get that idea?
> 
> As it doesn't seems to be explicitely documented, and I wanted some
> confirmation before posting, I had made a quick test with following
> script:
> 
>   var_dump($_GET['x']);
>   var_dump($x);
>   $x = 'bar';
>   var_dump($x);
>   var_dump($_GET['x']);
> 
> I requested the script with a query string of "x=foo".  The output:
> 
>   string(3) "foo" string(3) "foo" string(3) "bar" string(3) "foo"
> 
> (tested with PHP 5.2.13, FCGI, register_globals=On)
> 
> With $HTTP_GET_VARS instead of $_GET I get the same results
> (register_long_arrays=On), by the way.

ACK.  Session variables must be different, though.
 
>>>  Why is it logical to make global variables references to session
>>> variables (resp. let both reference the same variable/element)?
>> 
>> The (error-prone, unsafe) shortcut that register_globals allowed would
>> have been inconsistent otherwise.
> 
> IMHO only if the other parameters were also referenced.

Do you think it is a consistent implementation if you can read a session 
value using a global variable, but not modify it this way?
 
>>>>                    $*_VARS were first.
>>>
>>> According to the manual $HTTP_SESSION_VARS and $_SESSION are different
>>> variables, anyway.[1]
>>>
>>> [1] <http://www.php.net/manual/en/reserved.variables.session.php>
>> 
>> $_SESSION is a superglobal; $HTTP_SESSION_VARS is/was not (i.e., it needs
>> to be declared a global if it is to be accessed from local context).  But
>> I am quite certain that when both were still supported, if you modified
>> one, you modified the other (I have only PHP 5.5.9 to test with, where
>> there is no $HTTP_SESSION_VARS anymore).
> 
> The manual says:
> 
> | $HTTP_SESSION_VARS contains the same initial information, but is not
> | a superglobal. (Note that $HTTP_SESSION_VARS and $_SESSION are
> | different variables and that PHP handles them as such)

I *know* what the manual says.  That does not prove anything.

(Puzzling, but probably not relevant because of the newer PHP version:

$ php -r 'session_start(); var_dump($HTTP_SESSION_VARS["foo"]); 
$_SESSION["foo"] = "bar"; var_dump($HTTP_SESSION_VARS["foo"]); 
var_dump($_SESSION);'PHP Notice:  Undefined variable: HTTP_SESSION_VARS in 
Command line code on line 1
PHP Stack trace:
PHP   1. {main}() Command line code:0
NULL
PHP Notice:  Undefined variable: HTTP_SESSION_VARS in Command line code on 
line 1
PHP Stack trace:
PHP   1. {main}() Command line code:0
NULL
array(1) {
  'foo' =>
  string(3) "bar"
}

$ php -r 'session_start(); global $HTTP_SESSION_VARS; 
var_dump($HTTP_SESSION_VARS["foo"]); $_SESSION["foo"] = "bar"; 
var_dump($HTTP_SESSION_VARS["foo"]); var_dump($_SESSION);'
NULL
NULL
array(1) {
  'foo' =>
  string(3) "bar"
}

$ php -v
PHP 5.5.9-1 (cli) (built: Feb  8 2014 00:52:52) 
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.5.0, Copyright (c) 1998-2014 Zend Technologies
    with XCache v3.1.0, Copyright (c) 2005-2013, by mOo
    with Zend OPcache v7.0.3, Copyright (c) 1999-2014, by Zend Technologies
    with Xdebug v2.2.3, Copyright (c) 2002-2013, by Derick Rethans
    with XCache Optimizer v3.1.0, Copyright (c) 2005-2013, by mOo
    with XCache Cacher v3.1.0, Copyright (c) 2005-2013, by mOo
    with XCache Coverager v3.1.0, Copyright (c) 2005-2013, by mOo
)


PointedEars
-- 
    realism:    HTML 4.01 Strict
    evangelism: XHTML 1.0 Strict
    madness:    XHTML 1.1 as application/xhtml+xml
                                                    -- Bjoern Hoehrmann

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Thread

Completely stumped Richard Yates <richard@yatesguitar.com> - 2014-02-24 14:51 -0800
  Re: Completely stumped (still) Richard Yates <richard@yatesguitar.com> - 2014-02-24 15:53 -0800
    Re: Completely stumped (still) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-25 01:11 +0100
      Re: Completely stumped (still) Richard Yates <richard@yatesguitar.com> - 2014-02-24 16:24 -0800
        Re: Completely stumped (still) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-25 01:49 +0100
          Re: Completely stumped (still) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-25 03:37 +0100
            Re: Completely stumped (still) Jerry Stuckle <jstucklex@attglobal.net> - 2014-02-24 22:01 -0500
              Re: Completely stumped (still) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-25 19:38 +0100
                Re: Completely stumped (still) Jerry Stuckle <jstucklex@attglobal.net> - 2014-02-25 14:06 -0500
                Re: Completely stumped (still) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-25 20:28 +0100
                Re: Completely stumped (still) Jerry Stuckle <jstucklex@attglobal.net> - 2014-02-25 16:04 -0500
    Re: Completely stumped (still) Jerry Stuckle <jstucklex@attglobal.net> - 2014-02-24 20:59 -0500
      Re: Completely stumped (still) Richard Yates <richard@yatesguitar.com> - 2014-02-24 19:00 -0800
        Re: Completely stumped (still) Jerry Stuckle <jstucklex@attglobal.net> - 2014-02-24 22:04 -0500
          Re: Completely stumped (still) Richard Yates <richard@yatesguitar.com> - 2014-02-24 21:09 -0800
            Re: Completely stumped (still) Richard Yates <richard@yatesguitar.com> - 2014-02-24 21:30 -0800
      Re: Completely stumped (still) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-25 20:27 +0100
        Re: Completely stumped (still) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-25 20:34 +0100
          Re: Completely stumped (still) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-25 22:46 +0100
            Re: Completely stumped (still) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-25 23:30 +0100
              Re: Completely stumped (still) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-26 00:03 +0100
                Re: Completely stumped (still) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-26 00:29 +0100
                Re: Completely stumped (still) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-26 19:50 +0100
                Re: Completely stumped (still) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-26 22:20 +0100
                Re: Completely stumped (still) Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-27 00:21 +0100
        Re: Completely stumped (still) Richard Yates <richard@yatesguitar.com> - 2014-02-25 12:39 -0800
        Re: Completely stumped (still) Jerry Stuckle <jstucklex@attglobal.net> - 2014-02-25 16:06 -0500

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