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Can someone explain why the following doesn't work?

I have a PHP script that runs on a shared hosting account. The script should output my local time (for the time zone where I'm located, i.e. GMT-8:00, or PST.)

I'm reading documentation for time() PHP method that is supposed to return a Unix timestamp in UTC (or GMT). OK, good. So I need to subtract 8 hrs to get my local time, right?

So I'm doing this:

echo(date("n/j/Y, g:i:s A", time() - 28800));    //8hrs = 28800 seconds

But I'm getting time that is 5 hrs behind!

What can be wrong in a one-line statement as such?

PS. Sorry, if I'm asking the obvious. I'm coming from the world of .NET. I'm new to PHP.

ahmd0
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  • [`date_default_timezone_set`](http://php.net/manual/en/function.date-default-timezone-set.php) might be more useful and easier to use – scrowler Nov 21 '14 at 00:46
  • @scrowler: I'm not sure if I want to change any global settings. I'm using other libraries that may depend on it. – ahmd0 Nov 21 '14 at 00:50
  • I can't imagine what code should really care about the timezone of the server they're on. – Ja͢ck Nov 21 '14 at 01:15
  • @Ja͢ck: I need it for a local time of the brick-and-mortar store whose web site I'm working on. – ahmd0 Nov 21 '14 at 02:07

1 Answers1

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PHP's time() function will always return seconds since the epoch. The culprit for getting unexpected behavior is actually the date() function.

PHP's date() function will automatically convert the date to the current default timezone of PHP, which must be GMT - 3. This is why when you subtract 8 hours you're 5 hours behind.

Instead of using date(), you probably want to check in to gmdate(). Something like:

echo(gmdate("n/j/Y, g:i:s A", time() - 28800));

may be what you need.

Eric Ping
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  • Let me add that using a `DateTime` object makes date and timezones manipulation way more easier. Also see this [very good comment on gmmktime() on php.net](http://php.net/manual/en/function.gmmktime.php#83226) to understand why offsetting timestamps is less than ideal than actually dealing with timezones. :) – Benjamin C. Nov 21 '14 at 01:20
  • @EricPing: Thanks. Also found that the following works: `date("n/j/Y, g:i:s A", time() + 28800 - date("Z");`. Wow. No wonder people "love" PHP :) – ahmd0 Nov 21 '14 at 02:16