There is nothing wrong with that output at all. gmtime gives you exactly what it says - GMT time. So unless you happen to be in the GMT timezone, there will always be a difference. For example, when I run your script on my local machine I get: 
input time is 1160391190
gmtime gives: Mon Oct  9 10:53:10 2006
diff is: 28800

[download]
My local timezone is GMT+8 hours, so the output is correct.

Regards your local timezone being GMT+2, are you sure? Perhaps you are not taking something silly into account, like daylight savings?

As to what you should do about that, I'm afraid that I'm a little unclear on exactly what it is that you are trying to achieve - so perhaps you need to explain that a little more.

As a side note, you should try to avoid using $a and $b as variable names - they are special package global variables that are used by sort.

Cheers,
Darren :)

In reply to Re: working with epoch seconds by McDarren
in thread working with epoch seconds by jeanluca

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