Managing timezones for different users


I have a website where I have many users coming from different countries. Users can schedule a task based on their timezone. Now there is a cron running on the server after every min, the cron executes a script which checks if there are any scheduled task of any user and if so it does the needful.

Since my server is based in the US, the script executed by the cron considers the timezone of the US. What do I have to do in my script that will execute the user’s task based on user’s timezone instead of server’s timezone?

Thanks in advance for any ideas

One way would be to have all tasks scheduled and executed based on UTC and when a user views the tasks the app displays them based on their local time. You might need to get all users to specify their timezone (ie how many hours +/- of GMT (UTC). If the server is already set up to use one of the four US timezones then it’s best to do the schedulaing and execution based on that timezone with users specifying what their timezone

Thanks for your reply

is there any function in php that will tell me the time difference between the server timezone and the user’s timezone?

For example how much difference in hours is US timezone and Japan timezone?