I suspect what you are looking for is a hash of arrays. The following code may get you headed in the right direction:
use strict;
use warnings;
my %dailyRecords;
while (<DATA>) {
chomp;
next if ! length;
my @record = split; # Pull out the data fields
# Pull out Date and generate a date stamp
my @now = reverse ((localtime ($record[1]))[3..5]);
my $dateStamp = join '', map {sprintf '%04d', $_} @now;
# Append this record to list keyed by date stamp
push @{$dailyRecords{$dateStamp}}, [@record];
}
for (sort keys %dailyRecords) {
print "Day stamp: $_\n";
my @daysRecords = @{$dailyRecords{$_}};
print "@$_\n" for @daysRecords;
}
__DATA__
1149621887 1149623161 NG004193@net.NET 3 820 156 1
+7570249
1149621900 1149623197 NG004193@net.NET 1 648 80 0
+0
1149692376 1149694912 NG004193@net.NET 3 7932259 243 8
+5227944
1149695677 1149695693 Sinkbad@net.net 1 49385 0 0
+0
Prints:
Day stamp: 010600050007
1149621887 1149623161 NG004193@net.NET 3 820 156 17570249
1149621900 1149623197 NG004193@net.NET 1 648 80 00
Day stamp: 010600050008
1149692376 1149694912 NG004193@net.NET 3 7932259 243 85227944
1149695677 1149695693 Sinkbad@net.net 1 49385 0 00
DWIM is Perl's answer to Gödel