I assumed that the number after dot is 0.0001s. If not change the constant value BASE.

However, as date is not part of the time stamp, the result is ONLY meaningful under certain context. 
use strict;

use constant BASE => 10000;


print diff("00:17:12.0001", "23:18:09.0001");#this result would be mea
+ningless and wrong, if it's 23 of today, and 00 of tomorrow. But this
+ is not an implementation thing, the request is a little bit ...

sub diff {
    my ($t1, $t2) = @_;
    my ($h1, $m1, $s1, $ss1) = ($t1 =~ m/(\d+):(\d+):(\d+)\.(\d+)/);
    my ($h2, $m2, $s2, $ss2) = ($t2 =~ m/(\d+):(\d+):(\d+)\.(\d+)/);
    return (($h2 - $h1) * 3600 + ($m2 - $m1) * 60 + $s2 - $s1) * BASE 
++ $ss2 - $ss1;
}

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In reply to Re: Best way to do Time diff by pg
in thread Best way to do Time diff by Anonymous Monk

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