interesting date() question

bookbuyer2000

I created a test page that inserts the date and time into a log file. The line of code that I used is as follows:

$visit_time = date("Mj g:ia",time() - 25200);

But sometimes when other visitors from other locations visit that same test page, the date and time is an hour off.

For example, if I visit my own test page right now, the following gets logged:
Aug22 5:24pm
However, a couple seconds later, a visit from someone else will show up in my logs:
Aug22 6:24pm

I don't understand why that happens?

Weedpacket

How is the page being hosted? Is there more than one server?

bookbuyer2000

Hmm, good idea! I am not sure if there are multiple servers or not.

If there is more than one server, and it turns out that's the reason for the times being off, then is there anything I can do on my end (in my php code) so that the time is logged regardless which server is used?

Thank you.

NogDog

If using PHP5.1.0 or later (and if you aren't, why not?), use the [man]date_default_timezone_set/man function to set the desired timezone.

nrg_alpha

NogDog;10883439 wrote:
If using PHP5.1.0 or later (and if you aren't, why not?), use the [man]date_default_timezone_set/man function to set the desired timezone.

Ah, I keep forgetting about that myself. When I started building my site, I neglected to have:

ini_set('error_reporting', E_ALL);

But once I added this, I got these date / time errors.. I followed along in a thread here discussing the need to set timezones.. once I did, error was fixed. At first, I was rather perplexed, because my live version of the site has never revealed any problems to begin with (which if I understand correctly is due to security issues [preventing blatant errors from malicious prying eyes]). In any case, this point brings me to ask with regards to bookbuyer2000's issue.. if E_ALL is enabled, would the situation (at least on localhost) display some warnings / errors?

bookbuyer2000, I would be interesting in knowing if Nog's suggestion cleared it up. It seems that timezones and date functionality is somewhat intertwined. :o

Weedpacket

Some years back I got into the habit of using UTC for all recorded times and dates; that way it would never matter where the servers were located, so long as their clocks were set correctly. It made conversions into other timezones easier, too, because by being consistent I wouldn't have to wonder just which moment in time "2006-07-05 14:30:11" actually referred to.

nrg_alpha

Weedpacket;10883490 wrote:
Some years back I got into the habit of using UTC for all recorded times and dates; that way it would never matter where the servers were located, so long as their clocks were set correctly. It made conversions into other timezones easier, too, because by being consistent I wouldn't have to wonder just which moment in time "2006-07-05 14:30:11" actually referred to.

Sounds like a habit I should get into! 😉

So if I implemented:

date_default_timezone_set('UTC');

instead of my current selected default time zone, does this display the user's local time correctly? In otherwords, if viewed from users in the pacific as well as eastern timezones (with 12:00AM Friday being pacific) the date will be Friday for the pacific and Thursday for the eastern? (there's a 3 hour difference between pacific and eastern).

NogDog

No, you would have to set the default timezone to whatever zone you want displayed for that user, since the PHP script has no way to know what timezone the client is in unless you tell it (or it makes a best guess based on some IP-to-location code).