Shell Programming and Scripting

guys i have a Script was not written by me... that delete a particular file once it ages 7 days...
never the less, the script is not working as planed...

can someone help me out?

@fields = split( /\./, $logname );

$_ = $fields[1]; # get roll over time

# $1 $2 $3
# Y Y Y Y M M D D
/(\d\d\d\d)(\d\d)(\d\d)/;

$year = $1 - 1900; <-----WHY 1900??
$month = $2 - 1; <----- one month back???
$day = $3;

$time_of_log = timelocal( 0, 0, 0, $day, $month, $year );

if ($time_of_log < $time_expired)
{
# delete file
$filename = $dirname . "/" . $logname;
unlink $filename;


ERROR received,

Use of uninitialized value in subtraction (-) at ./script line 81.
Use of uninitialized value in subtraction (-) at ./script line 82.
Month '-1' out of range 0..11 at ./script line 85


I don't understand some of the lines here... is there a software that would show you the output for each line? i think that would help tremendously!

Message deleted, wrong input.

Actually, the assignment syntax in the script is correct, this is perl.

Oh sorry for that, I never noticed that and I dont any thing about PERL too.

$logname doe not have a value. It appears to be a filename with an embedded date/time stamp.

UNIX time (internal) is a number of seconds since an arbitrary starting time.... 1900 is the 'earliest' year, so 2006 would be year 106 which is 2006 - 1900.

Months start counting from zero ie., Jan = zero , Feb = 1....

Thanks jim... i believe the 1900 is the epoch year right?.. okay...
then something is wrong...
it seems that i earlier suspected that it could be the assignment of values, but reborg confirms that its correct... hmmmm...

The epoch year is 1970.

Code:

$ perl -e "printf localtime(0) . \"\\n\";"
Wed Dec 31 18:00:00 1969

My time zone is GMT-6 hours, so I have to add 6 hours for the epoch:

Code:

$ perl -e "printf localtime(0 +(60)*(60)*(6) ) . \"\\n\";"
Thu Jan  1 00:00:00 1970

The error message indicates that variables $1 , $2 and $3 are not initialized.

What value is assigned to $logname?