Re: Re: How to get TZ difference?

This doesn't work when localtime and gmtime are on different days (ie, in zone GMT+4 between 8:00pm and 11:59pm). Here's a fixed version:

#!/usr/bin/perl

@local=(localtime);
@gmt=(gmtime);
$diff=$gmt[2]-$local[2];
if ($gmt[5] > $local[5] || $gmt[7] > $local[7])
{
  $diff += 24;
}
elsif ($gmt[5] < $local[5] || $gmt[7] < $local[7])
{
  $diff -= 24;
}
[download]

Comment on Re: Re: How to get TZ difference? Download Code

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Re: Re: Re: How to get TZ difference? by sgifford (Prior) on Jun 28, 2003 at 17:55 UTC
This is a little shorter and more confusing. `@local=(localtime(time+$off_h6060)); @gmt=(gmtime(time+$off_h6060)); $diff=$gmt[2]-$local[2] + ($gmt[5] <=> $local[5] \|\| $gmt[7] <=> $local[7])*24;` [download]	[reply] [d/l]
Re: Re: Re: Re: How to get TZ difference? by dda (Friar) on Jul 06, 2003 at 06:38 UTC
Hi, Thanks for your idea. But let me ask you what is `$off_h` here? And I found that correct result occurs when I subtract `$gmt[2]` from `$local[2]`: `$diff=$local[2]-$gmt[2] + ($gmt[5] <=> $local[5] \|\| $gmt[7] <=> $local[7])*24;` [download] --dda	[reply] [d/l] [select]
Re: Re: Re: How to get TZ difference? by hsweet (Pilgrim) on Jun 28, 2003 at 22:51 UTC
thanks for the correction Time flies like an arrow, fruit flies like banannas	[reply]
Re^3: How to get TZ difference? by Anonymous Monk on Sep 08, 2014 at 09:42 UTC
you forgot to compare the months in case when we have last day of the month, around midnight it will return inccorect results	[reply]
Re^4: How to get TZ difference? by Anonymous Monk on Sep 14, 2016 at 18:37 UTC
`perl -e 'print ( ( (localtime)[2] - (gmtime)[2] + 12 ) % 24 - 12 )'` ...works across midnight, end of month, etc without all those pesky conditionals. Works because perl has a useful definition of modulo operator (%) for negative operands, but beware this can be compromised in certain situations. See perlop#Multiplicative-Operators.	[reply] [d/l]