$r->subprocess_env("REQUEST_URI") returns undef ?

From:
http://perl.apache.org/docs/2.0/api/Apache2/RequestRec.html# C_subprocess_env_

subprocess_env

Get/set the Apache subprocess_env table, or optionally set the value of
a named entry.

When the $key argument (string) is passed, it returns the corresponding
value (if such exists, or undef. The following two lines are equivalent:

$val = $r->subprocess_env($key);
$val = $r->subprocess_env->get($key);


Ok... Seems simple enough...

In my module if I do the following:

$r->subprocess_env;
my $uri = $ENV{REQUEST_URI};

The I get the URI.

But if I change the above to:

my $uri = $r->subprocess_env('REQUEST_URI');

I get undef.

Confused.

Tosh

--
McIntosh Cooey - Twelve Hundred Group LLC - http://www.1200group.com/

RE: $r->subprocess_env("REQUEST_URI") returns undef ?

At the risk of being kind of obvious, did you try $r->uri?

http://perl.apache.org/docs/2.0/api/Apache2/RequestRec.html# C_uri_

David

-----Original Message-----
From: Tosh Cooey [mailto:tosh@1200group.com]=20
Sent: Friday, January 15, 2010 10:42 AM
To: modperl@perl.apache.org
Subject: $r->subprocess_env('REQUEST_URI') returns undef ?

From:
http://perl.apache.org/docs/2.0/api/Apache2/RequestRec.html# C_subprocess_en=
v_

subprocess_env

Get/set the Apache subprocess_env table, or optionally set the value of=20
a named entry.

When the $key argument (string) is passed, it returns the corresponding=20
value (if such exists, or undef. The following two lines are equivalent:

$val =3D $r->subprocess_env($key);
$val =3D $r->subprocess_env->get($key);


Ok... Seems simple enough...

In my module if I do the following:

$r->subprocess_env;
my $uri =3D $ENV{REQUEST_URI};

The I get the URI.

But if I change the above to:

my $uri =3D $r->subprocess_env('REQUEST_URI');

I get undef.

Confused.

Tosh

--=20
McIntosh Cooey - Twelve Hundred Group LLC - http://www.1200group.com/

Re: $r->subprocess_env("REQUEST_URI") returns undef ?

On Friday 15 January 2010 19:41:45 Tosh Cooey wrote:
> When the $key argument (string) is passed, it returns the corresponding
> value (if such exists, or undef. The following two lines are equivalent:
>
> $val = $r->subprocess_env($key);
> $val = $r->subprocess_env->get($key);
>
>
> Ok... Seems simple enough...
>
> In my module if I do the following:
>
> $r->subprocess_env;
> my $uri = $ENV{REQUEST_URI};
>
> The I get the URI.
>
> But if I change the above to:
>
> my $uri = $r->subprocess_env('REQUEST_URI');
>
> I get undef.
>
Tosh, do you know what VOID context means in perl?

@list=function() # this list context
$scalar=function() # this is scalar context
function() # this is void context: the return value is ignored

Now, in void context and only then subprocess_env() calls

ap_add_common_vars(r);
ap_add_cgi_vars(r);

These 2 functions add such things like REQUEST_URI to the environment.

So, if you do it like this:

$r->subprocess_env; # void context
my $uri = $r->subprocess_env('REQUEST_URI');

it is very likely that you get the REQUEST_URI.

But as David pointed out, $r->uri is the much better way.

Torsten

Re: $r->subprocess_env("REQUEST_URI") returns undef ?

It's probably obvious, but $r kinda scares me. I guess I saw
subprocess_env in the docs and so that's where I stopped... What a
couple centimeters more would have done...

Thank-you David!!

Tosh


Ihnen, David wrote:
> At the risk of being kind of obvious, did you try $r->uri?
>
> http://perl.apache.org/docs/2.0/api/Apache2/RequestRec.html# C_uri_
>
> David
>
> -----Original Message-----
> From: Tosh Cooey [mailto:tosh@1200group.com]
> Sent: Friday, January 15, 2010 10:42 AM
> To: modperl@perl.apache.org
> Subject: $r->subprocess_env('REQUEST_URI') returns undef ?
>
> From:
> http://perl.apache.org/docs/2.0/api/Apache2/RequestRec.html# C_subprocess_env_
>
> subprocess_env
>
> Get/set the Apache subprocess_env table, or optionally set the value of
> a named entry.
>
> When the $key argument (string) is passed, it returns the corresponding
> value (if such exists, or undef. The following two lines are equivalent:
>
> $val = $r->subprocess_env($key);
> $val = $r->subprocess_env->get($key);
>
>
> Ok... Seems simple enough...
>
> In my module if I do the following:
>
> $r->subprocess_env;
> my $uri = $ENV{REQUEST_URI};
>
> The I get the URI.
>
> But if I change the above to:
>
> my $uri = $r->subprocess_env('REQUEST_URI');
>
> I get undef.
>
> Confused.
>
> Tosh
>

--
McIntosh Cooey - Twelve Hundred Group LLC - http://www.1200group.com/

Re: $r->subprocess_env("REQUEST_URI") returns undef ?

Ah... I assumed that $r->subprocess_env in VOID context was an expensive
operation as it populated $ENV (from what I had read) as one should try
to avoid it. I also find it non-intuitive that:

$r->subprocess_env; # void context
my $uri = $r->subprocess_env('REQUEST_URI');

is the same as

$r->subprocess_env;
my $uri = $ENV{REQUEST_URI};

But that's obviously just my lack of intuitiveness.

Yes, $r->uri is about a billion times more useful, thank-you again
David, and thanks for your help Torsten!

Tosh


Torsten Förtsch wrote:
> On Friday 15 January 2010 19:41:45 Tosh Cooey wrote:
>> When the $key argument (string) is passed, it returns the corresponding
>> value (if such exists, or undef. The following two lines are equivalent:
>>
>> $val = $r->subprocess_env($key);
>> $val = $r->subprocess_env->get($key);
>>
>>
>> Ok... Seems simple enough...
>>
>> In my module if I do the following:
>>
>> $r->subprocess_env;
>> my $uri = $ENV{REQUEST_URI};
>>
>> The I get the URI.
>>
>> But if I change the above to:
>>
>> my $uri = $r->subprocess_env('REQUEST_URI');
>>
>> I get undef.
>>
> Tosh, do you know what VOID context means in perl?
>
> @list=function() # this list context
> $scalar=function() # this is scalar context
> function() # this is void context: the return value is ignored
>
> Now, in void context and only then subprocess_env() calls
>
> ap_add_common_vars(r);
> ap_add_cgi_vars(r);
>
> These 2 functions add such things like REQUEST_URI to the environment.
>
> So, if you do it like this:
>
> $r->subprocess_env; # void context
> my $uri = $r->subprocess_env('REQUEST_URI');
>
> it is very likely that you get the REQUEST_URI.
>
> But as David pointed out, $r->uri is the much better way.
>
> Torsten
>

--
McIntosh Cooey - Twelve Hundred Group LLC - http://www.1200group.com/

Re: $r->subprocess_env("REQUEST_URI") returns undef ?

If $r scares you, are $c = $r->connection() and $s = $r->server()
truly terrifying :-)

cmac

On Jan 15, 2010, at 4:08 PM, Tosh Cooey wrote:

> It's probably obvious, but $r kinda scares me. I guess I saw
> subprocess_env in the docs and so that's where I stopped... What a
> couple centimeters more would have done...
>

Re: $r->subprocess_env("REQUEST_URI") returns undef ?

Not at all, I have no idea what they are, and ignorance is bliss!

Ah... Blessed ignorance...

Tosh


craig@animalhead.com wrote:
> If $r scares you, are $c = $r->connection() and $s = $r->server() truly
> terrifying :-)
>
> cmac
>
> On Jan 15, 2010, at 4:08 PM, Tosh Cooey wrote:
>
>> It's probably obvious, but $r kinda scares me. I guess I saw
>> subprocess_env in the docs and so that's where I stopped... What a
>> couple centimeters more would have done...
>>
>
>

--
McIntosh Cooey - Twelve Hundred Group LLC - http://www.1200group.com/