PHP time

[blm126]

Twey: Thanks for the tip I've never heard that before. Also I might have done my math wrong, but won't your code only run update() once a day. I think it should be this.

<?php
define('DATA_FILE', 'update_tracker.dat');
$c = floor(date('U') / 60 / 60);
//Removed the extra /24 above
$fc = file(DATA_FILE) or die('Failed to open file for reading.');
$l = $fc[0];

while($l++ < $c)
  update();

$f = fopen(DATA_FILE, 'w') or die('Failed to open file for writing.');
fwrite($f, $c);
fclose($f);
?>

[InNeedofHelp]

I understand the functions going on in that script, but can one of you please explain to me the theory behind the script? Like, the while loop in particular.

[blm126]

The file update_tracker.dat is used to keep track of when update() was last run.When the script loads it compares the current time($c) to the time held in update_tracker.dat($l).The while loop is used to run update() once for every hour that has passed.Then the current time is saved to update_tracker.dat

[Twey]

Also I might have done my math wrong, but won't your code only run update() once a day.

Yep, you're right. I was never good at maths.

[InNeedofHelp]

Dang this is confusing.
I get everything except, lets say someone accesses the page and that script is run, then 2 hours later the script is run again, that would write to the file something like 2:00pm, 4:00pm, but it would leave out 3:00pm so wouldn't the update not happen at 3?

[Twey]

That's what my code is for.

Breaking them both down into English, on each access, blm126's code will

• open the file and check if it's been run this hour;
• if so, run the function;
• update the file.

Mine will

• open the file and check when it was last run;
• for each hour in which it wasn't run, call the function once;
• update the file.

The updates won't necessarily happen on time, but they will all happen.

[InNeedofHelp]

Ooooohhhh.
Okay, now i get it. I'm not good with date functions nor file functions.
Thanks.