Date/time out of sequence

drwool

I've written a very simple script to track clicks on my web site. Links go to my little PHP program, passing a URL as an argument. The script writes a line to a log file and then redirects the user to the specified URL.

The weird thing is that sometimes the times recorded in the log file come out of sequence, and I can't understand why.

Here's the guts of the script:

$output = date("Y-m-d H:i ").getenv("REMOTE_ADDR")." ".$referer.':'.$id." ".$url."\n";
$fp = fopen ("$DOCUMENT_ROOT/../xlog/clicks.txt", "a");
fwrite ($fp, $output);
fclose ($fp);

I would think that since the date function returns the local date/time of the server (right?) that the lines in the log file should always be in strict time sequence. Generally they are, but now and then there will be a log line that's several hours out of sequence with the lines immediately before and after it. What could cause this?

drwool

To follow up, here's an example taken from my log showing activity early this morning. (I've removed everything but the dates):

2003-03-26 01:03
2003-03-26 01:24
2003-03-26 10:47 *
2003-03-26 01:59

The current time on the server is
Wed Mar 26 10:11:23 PST 2003

(I'm logged in right now looking at it.)
Note that the line marked with a * above shows a time that hasn't even happened yet... it's 36 minutes in the future!

Is the date function screwed up, or what?

ir4z0r

just a try:
date("Y-m-d H:i ",time())

drwool

Thanks for the suggestion. I tried it, but it hasn't changed anything.

I'm noticing that when I get these out-of-sequence times, they're not off by just any random amount. They always seem to be either 9 hours or 11 hours ahead of the actual time.

ir4z0r

another idea for debugging:

you probably have a hit counter?

Each time a visitor enters your site, create a file $hits, eg "134.hit",
"135.hit" and insert this number into your log line, too.
Afterwards you can compare file creation times and the time in
the corresponding line.

That's the only thing I'd do, otherwise, hmm - "they" are among us,
so just leave it as it is 😃

drwool

I just got word back from the tech support guy for my web host. He says it's some issue between the Apache web server and PHP, and they haven't been able to find a fix. So he suggests I use the exec function to get the date from the server instead.

Thanks for your suggestions, though!