Getting epoch time from gmt time stamp

Question

I have to calculate the date epoch time from a GMT timestamp, but I'm locally not in that timezone. My current local time is CEST.

So when I try to calculate the epoch time with

date -d "2017-08-05 10:10:10" "+%s"

I get

1501927810

But the given time is a GMT, and should therefore result in

1501927810

I was trying to manually add the difference of hours between the local time and the GMT with

date -d "2017-08-05 10:10:10 +2 hours" "+%F %T"

But that gives me

2017-08-05 11:10:10

why is there only +1 hour added!?

Answer 1

You can tell date to use GMT timezone by setting the environment variable TZ:

$ TZ=GMT date -d "2017-08-05 10:10:10" "+%s"
1501927810

Otherwise you would have to specify the date string as GMT (+0 hours, not 2):

$ date -d "2017-08-05 10:10:10 +0" "+%s"
1501927810