Perl - julian date

[Tigers!]

3 years I did some simple Perl at work and then stopped but need to do more.
The files I am looking at have a time/date stamp and I need to go backward for x days, gather the entries, manipulate etc:
I thought that if I get the julian date (j1) of the current date using $yday, subtract x to get a lower julian date (j2) bound then convert the julian back into dd/mm/yyyy. I would then search between the equivalents of j1 & j2.

The problem is to go from j2 into dd/mm/yyy. I cannot see to locate a function that is the reverse of $yday.
Does such a function exist?

(PS: I noted this thread http://www.sitepoint.com/forums/showthread.php?t=483502 which actually seems to do what I require but I'll ask my original question anyway.)

[chrisranjana]

cpan is your friend

http://search.cpan.org/search?query=...ulian&mode=all

[KevinR]

http://perldoc.perl.org/perlfaq4.html#How-can-I-compare-two-dates-and-find-the-difference%3f

[Tigers!]

Wonderful!
Thank you.

[KevinR]

You really shouldn't need to do any date conversions to do what you are trying to do. Get the modified date of the file and just subtract that many days (in seconds) from the modified date.

my $modified_date = (stat 'somefile.txt')[9];
my $date = $date - (86400 * 30);

then use $date to find files you are looking for.

86400 is the number of seconds in a day, so 86400 * 30 is 30 days ago.