Re: Event Handling

Alex Major wrote:

> Greetings all,
> 
> I'm currently looking at building a web application, however I've run into
> an area of development I've not come across before. The web site in its
> basic form allows users to send cars from a point and then the car will
> arrive at another point. When the car is set on its way, the start time,
> travel duration and end time are all known and stored in a MySQL database,
> what I would like to happen is that an event is triggered on the server at
> the end time and then an e-mail is sent to the user. This should happen
> regardless of whether someone is browsing the website or not.
> 
> I don't believe that I'll be able to solely use PHP, I have spent the
> afternoon trying to look at potential solutions but I have to admit I've
> drawn a blank. Google hasn't been helpful (64 pages so far), as any
> searches related to "event handling" bring up a load of JavaScript
> tutorials/help for 'onclick' events etc. I have searched through the PHP
> documentation and found "libevent"
> (http://www.php.net/manual/en/book.libevent.php ), I don't believe that is
> what I require (although in all honesty the lack of documentation on it
> means I'm quite in the dark as to its purpose). Another potential
> candidate I came across was a PHP/Java bridge
> (http://php-java-bridge.sourceforge.net/pjb/ ), whereby I could use the
> java virtual machine, register events with it and then callback PHP
> scripts, although this seems extremely long winded.
> 
> I was hoping that someone might have some experience with this kind of
> issue and could point me in the right direction. I'm sure I've missed
> something right in front of me.
> 
> Alex.

I think what you want is something to trigger a php script every
$period-of-time; if your host supports it, cron is the means of executing
an application at regular intervals down to a minute granularity. There are
some web-based cron services also, but they may not have the same
granularity as a locally based cron.


Cheers
-- 
David Robley

"Wow!" barked Tom, with a bow.
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