Shell Programming and Scripting

#!/usr/bin/perl
use Time::Local;
use POSIX qw(mktime strftime);

my $start=0, $end=0, $FMT="%Y%m%d.%H%M";

while($line=<STDIN>)
{
        # Split each line apart into the default $_ / @_ variable
        split("\\|",$line);
        # Last token is date.  Split apart date and time into two vars.
        ($mdy, $hms)=split(" ", @_[$#_]);
        #Split apart MM/DD/YYYY on /
        ($m, $d, $y)=split("/", $mdy);
        # Split apart HH:MM:SS on :
        ($hour, $min, $sec)=split(":", $hms);

        # Create a timestamp in epoch seconds from it.  $m-1 because Perl counts months 0-11
        $ldate=timelocal($sec, $min, $hour, $d, $m-1,$y);
        $min=$min-($min%15);    # chunks of 15 minutes

        # Check which date range it's in and change the output file as appropriate
        if($ldate >= $end)
        {
                $start=timelocal($sec,$min,$hour,$d,$m-1,$y);
                $end=$start + (15*60);
                $fname=sprintf("%s-%s.csv",
                        strftime("$FMT", localtime($start)),
                        strftime("$FMT", localtime($end)));

                FILE && close(FILE);
                open(FILE, ">$fname");
        }

        print FILE "$line";
}

FILE && close(FILE);
exit 0;