How to get the current time zone?

Question

In most of the examples I had seen:

time_zone_ptr zone( new posix_time_zone(\"MST-07\") ); 

But I just want to get the current time zone fo

Answer 1

In order to properly answer this question, it's important to understand that the time zone support in Boost is severely limited.

• It's primarily focused on POSIX time zones, which have several limitations. These limitations are discussed in the POSIX section of the timezone tag wiki, so I won't repeat them here.

• It has functions that work with IDs of IANA/Olson time zones, but it artificially maps these to POSIX values - which has the effect of flattening the time zone to a single point in history. These mappings are stored in a csv file in the Boost source code.

• The csv file hasn't been updated since April 2011, and there have been many changes to time zones since then. So, the mappings it does have are somewhat inaccurate.

In general, I would not recommend Boost for working with time zones. Instead, consider the ICU TimeZone Classes, which are part of the ICU project. You will find these to be fully portable, and they have full and correct time zone support.

It's worth mentioning that ICU is used in many popular applications. For example, the Google Chrome web browser gets it's time zone support from ICU.

In ICU, the current local system time zone is available as the default time zone. You can read more in the section "Factory Methods and the Default Timezone" in the ICU documentation.