Help - Deleting files, caching and server dispatcher

[halex]

1. What is the difference between these two delete functions (delete($file) and unlink($file) functions?)? In manual says that unlink($file) maybe not work on Windows platform. What to use to delete file on server (no matter of server OS)?

2. Is there some kind of caching? For example: I made SQL query and got some records. Then I delete few records (perform DB query). But I don't wan't to read again from database to display records that stayed alive. I want to keep them in memory and after deleting one record I remove this record from memorized array and then remove it physicaly from DB?

3. Is there some kind of server dispacher in PHP? For example: I wan't to have some live application that will send emails in midnight to person's that require that, and to delete records that are not valid anymore (because date has changed). This application will start exactly at midnigt, do what it has to do and hibernate.

[hand]

1.) unlink() works with Linux, Unix, WinNT, Win2000, WinXP but not with Win95/98. delete is a keyword and cannot be used as function name.
http://www.php.net/manual/en/function.unlink.php

2.) I never herd about such a mySQL functionality

3.) Linux/Unix cron http://www.webmachine.at/support/pw/p/cron.htm
or Win/Taskplaner Scheduler

[Weedpacket]

Originally posted by hand
1.) unlink() works with Linux, Unix, WinNT, Win2000, WinXP but not with Win95/98. delete is a keyword and cannot be used as function name.
http://www.php.net/manual/en/function.unlink.php

delete() isn't even a keyword. The manual entry for it reads (in full) "This is a dummy manual entry to satisfy those people who are looking for unlink() or unset() in the wrong place. See also: unlink() to delete files, unset() to delete variables."

As for unlink(), I've just tried it on Win95 with PHP4.2.2 and it worked fine. Since that succeeded, it was only curiosity that led me to try the fallback approach of "exec('del file.txt')" - that worked as well.

2.) I never herd about such a mySQL functionality

If by "in memory" is meant PHP's memory: read all the recordset into an array and use that as your cache. Use unset() to drop rows from the array, and use a SQL DELETE to drop the corresponding rows from the database. Similer synchronising can be done with regard to INSERT and UPDATE queries. Of course, inserts, deletes and updates by concurrently-running scripts won't be reflected in the cache - that would need a re-query.

[halex]

Thank you very much.
Yes I mean that caching.

And about email deamon... I need to ask my Apache administrator to have that functionality of sending email every midnight? I can send email with PHP when user click "Send me email" or automatialy during reistration... But how to do it without interference of myself - automatialy with that server deamon?
I got a link for some WebMachine PRO ServerSystem on Unix (cron service)...

and I deleted that previous message

[Weedpacket]

What you will be wanting is to set up a cron job - something your administrator should be able to help with.

As for how to go about it, I'm not familiar with running simultaneously as an Apache module and as a seperate executable - that's another story. It would be preferable if you could call PHP as a separate executable, since then the cron job could look like "php -f sendemail.php", where sendmail.php is the script to send the emails.

If the script has to be run via the web server, then - well, most *nix installations have an http client like lynx sitting around. You can use that to request the server to run the sendemail.php script. A first approximation to the syntax would be "lynx http://www.example.com/sendemail.php"

But in both scenarios, I make no claim to be an expert.

[hand]

@

http://www.php3.de/manual/en/function.delete.php
In ZendEngine2, delete is a keyword and cannot be used as function name.

[Weedpacket]

But PHP is not using ZendEngine2 except in alpha-test.

<?php delete();?>

PHP Fatal error: Call to undefined function: delete() in - on line 1

<?php delete;?>

PHP Notice: Use of undefined constant delete - assumed 'delete' in - on line 1

Don't confuse user comments with normative reference 🙂