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| Author |
Application Scope variables ?
|
|
|
| I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
| |
| Ruben van Engelenburg 2004-09-20, 9:00 am |
| aa wrote:
> I am migrating to PHP from ASP where there are the Application Scope
> variables which are accessible from any page on a website and which are
> used, in particular, for hit counters.
> Is there a similar mechanism in PHP?
Hi,
Yes there is, take a look at sessions:
http://nl3.php.net/manual/en/ref.session.php
Regards,
Ruben.
| |
| Virgil Green 2004-09-20, 3:57 pm |
| "Ruben van Engelenburg" <ruben@NOSPAM!.nl> wrote in message
news:414ebb56$0$65124$e4fe514c@news.xs4all.nl...
> aa wrote:
>
> Hi,
>
> Yes there is, take a look at sessions:
> http://nl3.php.net/manual/en/ref.session.php
Sessions are not the same as application scope, I don't believe.
I've seen references to shared memory schemes, but they are avaialble to the
entire computer, not just a single application (all sessions running under
the same site id, for example).
- Virgil
| |
|
| Dear Virgil,
your thinking is still too influenced by the rigid ASP structure.
Relax, open your mind and RTFM on sessions. :-)
Best Regards,
Lucas
"Virgil Green" <vjg@DESPAMobsydian.com> wrote in message news:<CnE3d.12658$yp2.5590@newssvr30.news.prodigy.com>...
> "Ruben van Engelenburg" <ruben@NOSPAM!.nl> wrote in message
> news:414ebb56$0$65124$e4fe514c@news.xs4all.nl...
>
> Sessions are not the same as application scope, I don't believe.
>
> I've seen references to shared memory schemes, but they are avaialble to the
> entire computer, not just a single application (all sessions running under
> the same site id, for example).
>
> - Virgil
| |
| Zurab Davitiani 2004-09-20, 8:58 pm |
| > your thinking is still too influenced by the rigid ASP structure.
> Relax, open your mind and RTFM on sessions. :-)
Session variables are not the same as application-level variables. ASP
offers an application framework, ASP *is* the framework.
Having said that, you can replicate functionality via PHP by either using
common files for variable storage/retrieval, or using a database. Some info
should be easily locatable by searching.
| |
|
| Dear Zurab,
sessions are stored as common files on the web server, one can
configure it accordingly to his/her needs so that data(variables) are
accesible from the required scope. Is there anything I missed?
Best Regards,
Lucas
Zurab Davitiani <agt@mindless.com> wrote in message news:<ALJ3d.21759$Lf5.2677@newssvr27.news.prodigy.com>...
>
> Session variables are not the same as application-level variables. ASP
> offers an application framework, ASP *is* the framework.
>
> Having said that, you can replicate functionality via PHP by either using
> common files for variable storage/retrieval, or using a database. Some info
> should be easily locatable by searching.
| |
| Virgil Green 2004-09-21, 8:56 am |
| "Lucas" <thelucas@directbox.com> wrote in message
news:fdb66b30.0409201432.a250159@posting.google.com...
> Dear Virgil,
>
> your thinking is still too influenced by the rigid ASP structure.
> Relax, open your mind and RTFM on sessions. :-)
I'm hardly influenced by ASP structure. I've never worked in ASP. I've read
the PHP manual sections on sessions many times before.
Please, enlighten me. Explain to me how sessions could be used to provide
the equivalent of application-scoped variables in ASP. The closest thing I
see is by sharing session IDs. That, of course, is a hack. There would be
nothing by default to synchronize access between multiple requests, so each
request could start with the same session info, update it and then spend
time merrily writing over each others changes. I could write my own custom
save handler, but I believe that writing such a handler to manage multiple
sessions as a single "session" would violate the spirit of the session and
lead to a maintenance nightmare.
I look forward to the details of your strategy.
- Virgil
| |
|
| Session will only make such a variable available within this session.
But I am talking about a variable available from any page from any session
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message
news:cip0pa$ig4$1$8300dec7@news.demon.co.uk...
>
> "aa" <aa@virgin.net> wrote in message
> news:415002f7$0$42212$ed2e19e4@ptn-nntp-reader04.plus.net...
retrieve[color=darkred]
>
> If you want to store variables between one page and another the PHP way is
> sessions. All you need is session_start() at the beginning of each script.
> This will create an empty $_SESSION array the first time, then give you
back
> everything you put in it.
>
> Note that you do not have to write the session data out to file manually
as
> PHP will do it automatically for you at the end of the script. It's all in
> the manual.
>
> --
> Tony Marston
>
> http://www.tonymarston.net
>
>
>
using[color=darkred]
>
>
| |
|
| "sessions are stored as common files on the web server"
Lucas,
1. Do these "common files" keep sitting on the disk after the relevant
session expired?
2. If they do, then for how long?
3. And how they might be accessed from another session?
Even if they can be accessable, I have difficulties to see a practical use
of them unless you keep track of every session file which is a tedious task
"Lucas" <thelucas@directbox.com> wrote in message
news:fdb66b30.0409202352.6263ac6f@posting.google.com...
> Dear Zurab,
>
> sessions are stored as common files on the web server, one can
> configure it accordingly to his/her needs so that data(variables) are
> accesible from the required scope. Is there anything I missed?
>
>
> Best Regards,
>
> Lucas
>
>
> Zurab Davitiani <agt@mindless.com> wrote in message
news:<ALJ3d.21759$Lf5.2677@newssvr27.news.prodigy.com>...[color=darkred]
using[color=darkred]
info[color=darkred]
| |
|
| Just to stream the discussion up - how a page hit conter in implemented in PHP?
In ASP you increment a relative Application scope variable every time a page is requested. This veraible is accessible from any session.
This variable is sitting in the memory as long as the Application (i.e. the website) is running.
If the Application is stopped, it fires an event "application_on_close" and on this event you write an application data to a file from which it can be recovered when the application is restarted.
How do I get the same effect in PHP?
"aa" <aa@virgin.net> wrote in message news:414eb86a$0$80627$ed2619ec@ptn-nntp-reader01.plus.net...
I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
| |
| Virgil Green 2004-09-21, 3:56 pm |
|
"aa" <aa@virgin.net> wrote in message
news:41505762$0$42260$ed2e19e4@ptn-nntp-reader04.plus.net...
> "sessions are stored as common files on the web server"
>
> Lucas,
>
> 1. Do these "common files" keep sitting on the disk after the relevant
> session expired?
> 2. If they do, then for how long?
> 3. And how they might be accessed from another session?
> Even if they can be accessable, I have difficulties to see a practical use
> of them unless you keep track of every session file which is a tedious
task
1. The Session management part of PHP cleans them up regularly.
2. Depends upon your settings in php.ini.
3. By using the same session ID for multiple "sessions"
And I find it highly impractical to attempt to use them constructively in
this manner. Better to understand this part of sessions to allow you to be
more careful when it comes to securing them. If one doesn't have cookies
enabled, one merely needs to put the appropriate variable=value in your URL
to hijaack a session.
- Virgil
| |
| Tony Marston 2004-09-21, 3:56 pm |
|
"aa" <aa@virgin.net> wrote in message
news:415055cf$0$42237$ed2e19e4@ptn-nntp-reader04.plus.net...
> Session will only make such a variable available within this session.
> But I am talking about a variable available from any page from any session
Then do what other people have already suggested:
(a) Store those variables in a database.
(b) Use a configuration which you can include() in every script.
There are no application-level variables in PHP which persist across pages
and sessions, so get used to it.
--
Tony Marston
http://www.tonymarston.net
> "Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message
> news:cip0pa$ig4$1$8300dec7@news.demon.co.uk...
> retrieve
> back
> as
> using
>
>
| |
| Tony Marston 2004-09-21, 3:56 pm |
| Reply-To: "Tony Marston" <tony@marston-home.demon.co.uk>
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"Virgil Green" <vjg@DESPAMobsydian.com> wrote in message
news:ifV3d.162$q67.47@newssvr11.news.prodigy.com...
> "Lucas" <thelucas@directbox.com> wrote in message
> news:fdb66b30.0409201432.a250159@posting.google.com...
>
> I'm hardly influenced by ASP structure. I've never worked in ASP. I've
> read
> the PHP manual sections on sessions many times before.
>
> Please, enlighten me. Explain to me how sessions could be used to provide
> the equivalent of application-scoped variables in ASP.
Store these variables in a database, or in a configuration file which you
can include() in every script.
PHP does not have any equivalent to application-scoped variables in ASP.
--
Tony Marston
http://www.tonymarston.net
> The closest thing I
> see is by sharing session IDs. That, of course, is a hack. There would be
> nothing by default to synchronize access between multiple requests, so
> each
> request could start with the same session info, update it and then spend
> time merrily writing over each others changes. I could write my own custom
> save handler, but I believe that writing such a handler to manage multiple
> sessions as a single "session" would violate the spirit of the session and
> lead to a maintenance nightmare.
>
> I look forward to the details of your strategy.
>
> - Virgil
>
>
| |
| Tony Marston 2004-09-21, 3:56 pm |
| To implement a hit counter in PHP I would use a database table.
There is no such thing as being able to detect when the application is closed. The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser? That is impossible to tell.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:415058ee$0$42257$ed2e19e4@ptn-nntp-reader04.plus.net...
Just to stream the discussion up - how a page hit conter in implemented in PHP?
In ASP you increment a relative Application scope variable every time a page is requested. This veraible is accessible from any session.
This variable is sitting in the memory as long as the Application (i.e. the website) is running.
If the Application is stopped, it fires an event "application_on_close" and on this event you write an application data to a file from which it can be recovered when the application is restarted.
How do I get the same effect in PHP?
"aa" <aa@virgin.net> wrote in message news:414eb86a$0$80627$ed2619ec@ptn-nntp-reader01.plus.net...
I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
| |
| Gordon Burditt 2004-09-21, 3:56 pm |
| >Just to stream the discussion up - how a page hit conter in implemented in PHP?
I'd use a database:
UPDATE hit_count set count=count+1, last=now() where url='...';
or if I really wanted details for each hit, add an entry to a hit_log table,
logging time, URL, and perhaps other stuff like IP, user name, session, referrer, etc.
>In ASP you increment a relative Application scope variable every time a page is
>requested. This veraible is accessible from any session.
Besides hit counters, of what *USE* is such a variable?
It can be accessed from (and messed up by) so many different
concurrent sessions that any significant read/write use will have
to worry about locking issues. Does ASP even guarantee that several
sessions each doing the equivalent of $hitcount++; will be atomic
and not lose counts (on a multiprocessor machine, possibly)?
Assume $last_server is the ID of the last waitperson assigned to a table (and
it's one of those "Application-scope" variables.
IDs run from 1 to $max_server. You want to assign them in turn, round-robin.
$last_server++;
if ($last_server > $max_server) { $last_server = 1; }
$this_server = $last_server;
.... assign $this_server to serve the food for this order ...
Now, how do you write that (or its equivalent in ASP) so it's
multi-session, multi-processor safe? You don't assign the same
server two orders a row. You don't skip anyone. Not even if a bunch
of orders come in simultaneously.
I also wouldn't be too pleased to learn that I'd lose several days
worth of changes to that variable (kept only in memory) if the
machine crashed. In particular, losing a variable like 'next invoice
number to assign' kept in memory only would be a real nuisance.
>This variable is sitting in the memory as long as the Application (i.e. the website) is
>running.
Which means you can lose it at any time if the Application is running.
>If the Application is stopped, it fires an event "application_on_close" and on this
>event you write an application data to a file from which it can be recovered when the
>application is restarted.
And if the application, or system, crashes? How often do you actually intentionally
shut down a web server (besides applying security patches)? In my experience, this
is MUCH less often than CPU fan failure or power supply failure.
>How do I get the same effect in PHP?
What do you need it for? I think it makes an unreliable hit counter and it's not
good for much else.
Gordon L. Burditt
| |
| Gordon Burditt 2004-09-21, 3:56 pm |
| >To implement a hit counter in PHP I would use a database table.
Agreed.
>There is no such thing as being able to detect when the application is closed. The
>client simply stops sending requests to your web site. Is he still reading the last
>page? Has he jumped to another site? Has he closed the browser? That is impossible to
>tell.
That's a SESSION, not the application. And no, you can't tell when
it's closed except by timeout or occasionally by someone clicking
on "LOG OUT".
The APPLICATION being referred to is the web server itself. Shutting
it down might be done with commands like "apachectl stop" or
"shutdown", or tripping over the power cord. In my experience when
the web server is shut down, it is shut down quite rudely by CPU
fan failure, more than 50% of the time.
Gordon L. Burditt
| |
|
| "Does ASP even guarantee that several sessions each doing the equivalent of
$hitcount++; "
ASP' application is an object with a method "lock" to handle attempts to
change a variable from two or more sessions at a time. I do not know is it
guaranties something, but it works.
So if there is nothing like that in PHP - thanks - you saved me time lokinmg
for something which is not there.
"Gordon Burditt" <gordonb.a6hin@burditt.org> wrote in message
news:cipte4$qal@library2.airnews.net...
in PHP?[color=darkred]
>
> I'd use a database:
> UPDATE hit_count set count=count+1, last=now() where url='...';
> or if I really wanted details for each hit, add an entry to a hit_log
table,
> logging time, URL, and perhaps other stuff like IP, user name, session,
referrer, etc.
>
page is[color=darkred]
>
> Besides hit counters, of what *USE* is such a variable?
> It can be accessed from (and messed up by) so many different
> concurrent sessions that any significant read/write use will have
> to worry about locking issues. Does ASP even guarantee that several
> sessions each doing the equivalent of $hitcount++; will be atomic
> and not lose counts (on a multiprocessor machine, possibly)?
>
> Assume $last_server is the ID of the last waitperson assigned to a table
(and
> it's one of those "Application-scope" variables.
> IDs run from 1 to $max_server. You want to assign them in turn,
round-robin.
>
> $last_server++;
> if ($last_server > $max_server) { $last_server = 1; }
> $this_server = $last_server;
> ... assign $this_server to serve the food for this order ...
>
> Now, how do you write that (or its equivalent in ASP) so it's
> multi-session, multi-processor safe? You don't assign the same
> server two orders a row. You don't skip anyone. Not even if a bunch
> of orders come in simultaneously.
>
>
> I also wouldn't be too pleased to learn that I'd lose several days
> worth of changes to that variable (kept only in memory) if the
> machine crashed. In particular, losing a variable like 'next invoice
> number to assign' kept in memory only would be a real nuisance.
>
the website) is[color=darkred]
>
> Which means you can lose it at any time if the Application is running.
>
and on this[color=darkred]
recovered when the[color=darkred]
>
> And if the application, or system, crashes? How often do you actually
intentionally
> shut down a web server (besides applying security patches)? In my
experience, this
> is MUCH less often than CPU fan failure or power supply failure.
>
>
> What do you need it for? I think it makes an unreliable hit counter and
it's not
> good for much else.
>
> Gordon L. Burditt
| |
|
| > Then do what other people have already suggested:
Actually I have suggested that myself, but hoped that there is more elegant
solution
Thanks.
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message
news:cips55$sjm$1$8300dec7@news.demon.co.uk...
>
> "aa" <aa@virgin.net> wrote in message
> news:415055cf$0$42237$ed2e19e4@ptn-nntp-reader04.plus.net...
session[color=darkred]
>
> Then do what other people have already suggested:
> (a) Store those variables in a database.
> (b) Use a configuration which you can include() in every script.
>
> There are no application-level variables in PHP which persist across pages
> and sessions, so get used to it.
>
> --
> Tony Marston
>
> http://www.tonymarston.net
>
>
>
manually[color=darkred]
ASP[color=darkred]
Some[color=darkred]
>
>
| |
|
| "There is no such thing as being able to detect when the application is closed.The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser?
That is impossible to tell."
That is not necessary to tell, for the actions of a particular visitor are not relevant.
As it happens with Windows/IIS/ASP, Application can either be closed manually, or it times out if there are not requests for a preset period of time. In other words, application closes when the last active session times out.
Is this the case with apache server?
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:cipsgh$npr$1$8302bc10@news.demon.co.uk...
To implement a hit counter in PHP I would use a database table.
There is no such thing as being able to detect when the application is closed. The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser? That is impossible to tell.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:415058ee$0$42257$ed2e19e4@ptn-nntp-reader04.plus.net...
Just to stream the discussion up - how a page hit conter in implemented in PHP?
In ASP you increment a relative Application scope variable every time a page is requested. This veraible is accessible from any session.
This variable is sitting in the memory as long as the Application (i.e. the website) is running.
If the Application is stopped, it fires an event "application_on_close" and on this event you write an application data to a file from which it can be recovered when the application is restarted.
How do I get the same effect in PHP?
"aa" <aa@virgin.net> wrote in message news:414eb86a$0$80627$ed2619ec@ptn-nntp-reader01.plus.net...
I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
| |
| Tony Marston 2004-09-21, 8:55 pm |
| If by "application" you mean "web server" then it is not common practice to stop the web server when the last client has finished. A web server usually runs 24/7 so that it is available whenever somebody wants to access it. If you are talking about a closed application such as on a company's intranet which may only be available during certain times of day then shutting down the web server does nothing more than shut down the web server. There is no concept of running any closedown routines for whatever application may have been accessed during the time the web server was running. A web server like apache is merely a vehicle for servicing HTTP requests. It serves up html documents or php documents or whatever. Those documents are the application. It has no knowledge of any particular application which it may run. Why should it?
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:41508cf8$0$17960$ed2619ec@ptn-nntp-reader02.plus.net...
"There is no such thing as being able to detect when the application is closed.The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser?
That is impossible to tell."
That is not necessary to tell, for the actions of a particular visitor are not relevant.
As it happens with Windows/IIS/ASP, Application can either be closed manually, or it times out if there are not requests for a preset period of time. In other words, application closes when the last active session times out.
Is this the case with apache server?
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:cipsgh$npr$1$8302bc10@news.demon.co.uk...
To implement a hit counter in PHP I would use a database table.
There is no such thing as being able to detect when the application is closed. The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser? That is impossible to tell.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:415058ee$0$42257$ed2e19e4@ptn-nntp-reader04.plus.net...
Just to stream the discussion up - how a page hit conter in implemented in PHP?
In ASP you increment a relative Application scope variable every time a page is requested. This veraible is accessible from any session.
This variable is sitting in the memory as long as the Application (i.e. the website) is running.
If the Application is stopped, it fires an event "application_on_close" and on this event you write an application data to a file from which it can be recovered when the application is restarted.
How do I get the same effect in PHP?
"aa" <aa@virgin.net> wrote in message news:414eb86a$0$80627$ed2619ec@ptn-nntp-reader01.plus.net...
I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
| |
| Zurab Davitiani 2004-09-22, 3:55 am |
| Lucas wrote:
> sessions are stored as common files on the web server, one can
> configure it accordingly to his/her needs so that data(variables) are
> accesible from the required scope. Is there anything I missed?
Yes. Application level variables in this case means that the variables are
shared within the defined frame of an application. i.e. the variables are
shared between different sessions or clients accessing the "application."
For more information, look up Application and Session objects within the
ASP framework; or even Java servlets.
| |
|
| You missed me, Tony. Of course I did not mean application==webserver
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:ciqd4r$o7m$1$830fa7a5@news.demon.co.uk...
If by "application" you mean "web server" then it is not common practice to stop the web server when the last client has finished. A web server usually runs 24/7 so that it is available whenever somebody wants to access it. If you are talking about a closed application such as on a company's intranet which may only be available during certain times of day then shutting down the web server does nothing more than shut down the web server. There is no concept of running any closedown routines for whatever application may have been accessed during the time the web server was running. A web server like apache is merely a vehicle for servicing HTTP requests. It serves up html documents or php documents or whatever. Those documents are the application. It has no knowledge of any particular application which it may run. Why should it?
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:41508cf8$0$17960$ed2619ec@ptn-nntp-reader02.plus.net...
"There is no such thing as being able to detect when the application is closed.The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser?
That is impossible to tell."
That is not necessary to tell, for the actions of a particular visitor are not relevant.
As it happens with Windows/IIS/ASP, Application can either be closed manually, or it times out if there are not requests for a preset period of time. In other words, application closes when the last active session times out.
Is this the case with apache server?
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:cipsgh$npr$1$8302bc10@news.demon.co.uk...
To implement a hit counter in PHP I would use a database table.
There is no such thing as being able to detect when the application is closed. The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser? That is impossible to tell.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:415058ee$0$42257$ed2e19e4@ptn-nntp-reader04.plus.net...
Just to stream the discussion up - how a page hit conter in implemented in PHP?
In ASP you increment a relative Application scope variable every time a page is requested. This veraible is accessible from any session.
This variable is sitting in the memory as long as the Application (i.e. the website) is running.
If the Application is stopped, it fires an event "application_on_close" and on this event you write an application data to a file from which it can be recovered when the application is restarted.
How do I get the same effect in PHP?
"aa" <aa@virgin.net> wrote in message news:414eb86a$0$80627$ed2619ec@ptn-nntp-reader01.plus.net...
I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
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| Hi aa,
"aa" <aa@virgin.net> wrote in message news:<415055cf$0$42237$ed2e19e4@ptn-nntp-reader04.plus.net>...
> Session will only make such a variable available within this session.
> But I am talking about a variable available from any page from any session
using real sessions(!=cookie emulation) makes it possible to access
data from any client application, independent of the one that created
it. However, I did read some stuff on ALV, and admit it's much more
sophisticated, does anyone know if there are any improvements in PHP5?
[color=darkred]
>
> "Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message
> news:cip0pa$ig4$1$8300dec7@news.demon.co.uk...
> retrieve
> back
> as
> using
> info
| |
| Tony Marston 2004-09-22, 8:57 pm |
| Then the answer is easy. apache has no concept of an "application". It is simply a web server which waits for requests and issues responses. PHP also has no concept of an "application" in the way you describe for IIS/ASP. However, you can achieve the same functionality by using config files, sessions, and/or databases.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:41515c7c$0$69739$ed2619ec@ptn-nntp-reader01.plus.net...
You missed me, Tony. Of course I did not mean application==webserver
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:ciqd4r$o7m$1$830fa7a5@news.demon.co.uk...
If by "application" you mean "web server" then it is not common practice to stop the web server when the last client has finished. A web server usually runs 24/7 so that it is available whenever somebody wants to access it. If you are talking about a closed application such as on a company's intranet which may only be available during certain times of day then shutting down the web server does nothing more than shut down the web server. There is no concept of running any closedown routines for whatever application may have been accessed during the time the web server was running. A web server like apache is merely a vehicle for servicing HTTP requests. It serves up html documents or php documents or whatever. Those documents are the application. It has no knowledge of any particular application which it may run. Why should it?
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:41508cf8$0$17960$ed2619ec@ptn-nntp-reader02.plus.net...
"There is no such thing as being able to detect when the application is closed.The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser?
That is impossible to tell."
That is not necessary to tell, for the actions of a particular visitor are not relevant.
As it happens with Windows/IIS/ASP, Application can either be closed manually, or it times out if there are not requests for a preset period of time. In other words, application closes when the last active session times out.
Is this the case with apache server?
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:cipsgh$npr$1$8302bc10@news.demon.co.uk...
To implement a hit counter in PHP I would use a database table.
There is no such thing as being able to detect when the application is closed. The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser? That is impossible to tell.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:415058ee$0$42257$ed2e19e4@ptn-nntp-reader04.plus.net...
Just to stream the discussion up - how a page hit conter in implemented in PHP?
In ASP you increment a relative Application scope variable every time a page is requested. This veraible is accessible from any session.
This variable is sitting in the memory as long as the Application (i.e. the website) is running.
If the Application is stopped, it fires an event "application_on_close" and on this event you write an application data to a file from which it can be recovered when the application is restarted.
How do I get the same effect in PHP?
"aa" <aa@virgin.net> wrote in message news:414eb86a$0$80627$ed2619ec@ptn-nntp-reader01.plus.net...
I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
| |
| Michael Fesser 2004-09-23, 3:55 am |
| .oO(Tony Marston)
>[...]
Is it one of OE's many "features" to answer to an HTML-posting in HTML
instead of plain text?
It's not really funny having to download a bloated 305-lines posting
(thanks to the HTML) with just 4 lines of new text.
Fup2 poster
Micha
| |
|
| In ASP an application is an object created when a first request is made to a website. This object seats in the memory and contains methods and properties some of the properties can be created and modified from ASP code.
As a websever can serve more them one website and some websites might be visited just several times a day, there is little point to keep all these website objects in the memory all the time. For that purpose, if a website does not receive requestes for certain time (which can be preset on the websrver), the Application object is destroyed and memory reclaimed. Not to loose data stored in the Object, it allows to write this data onto disk before being destroyed.
If I understand correctly, PHP does not maintain such an object and the variables relevant to the whole website need to be written onto disk before a relevant session expires.
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:cit5a1$2ov$1$8302bc10@news.demon.co.uk...
Then the answer is easy. apache has no concept of an "application". It is simply a web server which waits for requests and issues responses. PHP also has no concept of an "application" in the way you describe for IIS/ASP. However, you can achieve the same functionality by using config files, sessions, and/or databases.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:41515c7c$0$69739$ed2619ec@ptn-nntp-reader01.plus.net...
You missed me, Tony. Of course I did not mean application==webserver
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:ciqd4r$o7m$1$830fa7a5@news.demon.co.uk...
If by "application" you mean "web server" then it is not common practice to stop the web server when the last client has finished. A web server usually runs 24/7 so that it is available whenever somebody wants to access it. If you are talking about a closed application such as on a company's intranet which may only be available during certain times of day then shutting down the web server does nothing more than shut down the web server. There is no concept of running any closedown routines for whatever application may have been accessed during the time the web server was running. A web server like apache is merely a vehicle for servicing HTTP requests. It serves up html documents or php documents or whatever. Those documents are the application. It has no knowledge of any particular application which it may run. Why should it?
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:41508cf8$0$17960$ed2619ec@ptn-nntp-reader02.plus.net...
"There is no such thing as being able to detect when the application is closed.The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser?
That is impossible to tell."
That is not necessary to tell, for the actions of a particular visitor are not relevant.
As it happens with Windows/IIS/ASP, Application can either be closed manually, or it times out if there are not requests for a preset period of time. In other words, application closes when the last active session times out.
Is this the case with apache server?
"Tony Marston" <tony@NOSPAM.demon.co.uk> wrote in message news:cipsgh$npr$1$8302bc10@news.demon.co.uk...
To implement a hit counter in PHP I would use a database table.
There is no such thing as being able to detect when the application is closed. The client simply stops sending requests to your web site. Is he still reading the last page? Has he jumped to another site? Has he closed the browser? That is impossible to tell.
--
Tony Marston
http://www.tonymarston.net
"aa" <aa@virgin.net> wrote in message news:415058ee$0$42257$ed2e19e4@ptn-nntp-reader04.plus.net...
Just to stream the discussion up - how a page hit conter in implemented in PHP?
In ASP you increment a relative Application scope variable every time a page is requested. This veraible is accessible from any session.
This variable is sitting in the memory as long as the Application (i.e. the website) is running.
If the Application is stopped, it fires an event "application_on_close" and on this event you write an application data to a file from which it can be recovered when the application is restarted.
How do I get the same effect in PHP?
"aa" <aa@virgin.net> wrote in message news:414eb86a$0$80627$ed2619ec@ptn-nntp-reader01.plus.net...
I am migrating to PHP from ASP where there are the Application Scope variables which are accessible from any page on a website and which are used, in particular, for hit counters.
Is there a similar mechanism in PHP?
| |
| Tony Marston 2004-09-23, 3:56 pm |
|
"aa" <aa@virgin.net> wrote in message
news:4152a0a2$0$17948$ed2619ec@ptn-nntp-reader02.plus.net...
> In ASP an application is an object created when a first request is made to
> a
> website. This object seats in the memory and contains methods and
> properties
> some of the properties can be created and modified from ASP code.
> As a websever can serve more them one website and some websites might be
> visited just several times a day, there is little point to keep all these
> website objects in the memory all the time. For that purpose, if a website
> does not receive requests for certain time (which can be preset on the
> websrver), the Application object is destroyed and memory reclaimed. Not
> to
> loose data stored in the Object, it allows to write this data onto disk
> before being destroyed.
> If I understand correctly, PHP does not maintain such an object and the
> variables relevant to the whole website need to be written onto disk
> before
> a relevant session expires.
Correct. PHP does not understand the concept of "application" as you
describe it.
From your description it seems to be more of a function of the web server as
only the web server can create the object on the first request, and destroy
the object if there have not been any requests for a period of time.
If you want to emulate this with PHP you must read in the variables with
every request and write out any changes before the script dies. You can use
session files or database tables. It may be possible to use data in shared
memory, but you would have to write your own routines for loading it and
destroying it. Personally I wouldn't bother as the overhead of reading in
data with every request is so small that it's not worth the effort to
replace it with something more flashy.
--
Tony Marston
http://www.tonymarston.net
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