In OS X: getting the timezone in PHP or from a command prompt in Terminal

Question

For some reason, the PHP developers decided a while ago that they don't want to trust the timezone information available from the system. So your PHP script under OSX, if it is going to use any time/date function, must do something like: ``` date_default_timezone_set ("Europe/London"); ``` Now, I don't know where on the planet my script is going to be executed, and it's unreasonable to expect an ordinary user to have to supply a timezone string - the user is going to say, quite reasonably, that they've already set that in the System prefs so why can't I look for it there. So, up to now, I've been doing: ``` $cmd = '/usr/sbin/systemsetup -gettimezone'; exec ($cmd, $results, $result); ``` and picking through the results to get a string to use. So far so good. Now I observe two things: The man page for this command insists I need "at least admin priv to run". I tried it on an account without admin priv and this is indeed the case, so long term I'll need another approach. I happened to lo…

Accepted Answer

OS X stores the system's time zone by making a symbolic link from /etc/localtime to the correct time zone file under /usr/share/zoneinfo/. See "man 3 tzset".

Since you're already in PHP, you could do this to get the time zone's name:

```
$systemZoneName = readlink('/etc/localtime');
$systemZoneName = substr($systemZoneName, strlen ('/usr/share/zoneinfo/'));
```

Then, to make that the default time zone you could do this:

```
date_default_timezone_set ($systemZoneName);
```

You should also be able to do

```
ini_set('date.timezone', $systemZoneName);
```

or, if you just need a DateTimeZone object,

```
$systemZone = new DateTimeZone ($systemZoneName);
```

In OS X: getting the timezone in PHP or from a command prompt in Terminal

Solution

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