unix time conversion wrong?
by Benno Schmid on 04/20/05 at 07:25:11

Hi,
i just tried your unix time conversion application and it seems as if there is something wrong with it.
When i use the last full hour (4/20/2005 13:00:00) i get 1114002000, whereas other converter and the command perl -e "print time - time%3600" give me 1113994800.
I also got wrong results with another time i had to use for a riddle.
Please look at the code again, i don't know javascript so i can't spot the bug.
Greetings, Benno

Re: unix time conversion wrong?
by Robert Fogt on 04/20/05 at 16:54:42

I checked using Perl and it is correct as it is.

I used the following code:
[pre]
#!/usr/bin/perl

$first_string = gmtime(1113994800);
$second_string = gmtime(1114002000);
print "$first_string\n$second_string";
[/pre]

When run, the output is:
[pre]
Wed Apr 20 11:00:00 2005
Wed Apr 20 13:00:00 2005
[/pre]

The second string is the correct time both according to Perl and according to the JavaScript code.

Though I am using ActivePerl on Windows. That should not matter but it is possible a Linux Perl installation is giving different result. Try running the above code and seeing what your result is.

Re: unix time conversion wrong?
by Benno Schmid on 04/21/05 at 06:29:20

Ah, you use gmtime which prints out Greenwich Mean Time, which is shifted by two hours in my time zone (CEST). This explains the differences, though I would find it more natural to use local time.

Re: unix time conversion wrong?
by Robert Fogt on 04/21/05 at 13:13:09

The JavaScript version uses Universal Time Coordinated, which is almost the same thing as Greenwich Mean Time. It can differ by up to a second or two.  I do test it with GMT time though.

I can probably add a Local Time to the conversion page too. I think it might even be on my to-do list.  I will see what I can come up with.

Go Back | Archive Index