Question

I need to get the UTC offset of the current time zone in Perl in a cross platform (Windows and various flavors of Unix) way. It should meet this format:

zzzzzz, which represents ±hh:mm in relation to UTC

It looks like I should be able to get it via strftime(), but it doesn’t appear to be consistent.

Unix:

Input: perl -MPOSIX -e "print strftime(\"%z\", localtime());"
Output: -0700

Windows:

Input: perl -MPOSIX -e "print strftime(\"%z\", localtime());"
Output: Mountain Standard Time

While it appears that Unix is giving me what I want (or at least something close), Windows is not. I’m pretty sure I can do it with Date::Time or similar, but I’d really like to not have any dependencies that I can’t guarantee a user will have due to our wide install base.

Am I missing something obvious here? Thanks in advance.

Answer 1

Time::Local should do the trick

use Time::Local;
@t = localtime(time);
$gmt_offset_in_seconds = timegm(@t) - timelocal(@t);