my %month = (
    jan => 1,
    feb => 2,
    ...
);
m/webadmin_([^_]+)_(\d+)_(\d{4})\.log/;
my ($month, $day, $year) = ($1, $2, $3);
my $new_filename = sprintf "%04d-%02d-%02d", $year, $month{$month}, $d
+ay;
[download]

You can combine that with a Schwartzian Transform.

use strict;

my @files = qw (webadmin_jul_10_2007.log
webadmin_jul_11_2007.log
webadmin_jul_12_2007.log
webadmin_jul_13_2007.log
webadmin_jul_14_2007.log
webadmin_jul_7_2007.log
webadmin_jul_8_2007.log
webadmin_jul_9_2007.log);

sub bydate {
   # Extract non-numeric and date 
   # Assumes text after date is the same
   my ($afront, $aday, $ayear) = $a =~ /^([[:alpha:]_]+)(\d+)_(\d+)/;
   my ($bfront, $bday, $byear) = $b =~ /^([[:alpha:]_]+)(\d+)_(\d+)/;
   my $retn = ($afront cmp $bfront);

   $retn = ($ayear <=> $byear) if $retn == 0;
   $retn = ($aday  <=> $bday)  if $retn == 0;
   
   return $retn
}

my @sorted = sort bydate @files;
local $" = "\n";
print "@sorted\n";
[download]

If you can be assured that your files are not altered after the log moves on (big assumption that must be verified), you might just use a 'stat' mtime as your sort key.

Also, if you want to do a system call using backtics, you can let the file system sort your files for you (assuming UNIX).

my $files = `/bin/ls -1tr $dir`;
my @files = grep { ! -d "$dir/$_" and ! /user.log/ } split /\n/, $file
+s;
[download]

Respected monks

Thank You all for your prompt replies and my problem has been sorted out. I could really learn a lot from each and every idea that has beem posted to me. Here in Perlmonks site I have evoled myself and have learnt a lot.

Snopal

This is also a very good idea to sort the files up on the modification time as the latest file is the one which is modified according to the dates.

This also has done the trick for me but can you please explain me wat does "1" do there becos since -t and -r we use them for the modification time and to reverse sort. But "1" i was not able to find wat does 1 do ...

Any ways thank uo very much for ur solution too.

Sushil Kumar

use Sort::Key::Multi 'iiikeysort'; 
  # the 'iii' stands for three integer keys

my (%month, $month);
$month{$_} = ++$month for qw(jan feb mar apr ...);

@sorted = iiikeysort { /^webadmin_(\w+)_(\d+)_(\d+)\.log$/;
                        ($3, $month{$1}, $2) } @filenames;
[download]

The reason that "it is taking the elements as strings even though i gave it to sort in numerical way" is because the filenames start with text, not numbers. If they were formatted as 7_jul_2007_webadmin.log, then your sort idea would have worked (until 1_aug_webadmin.log, at least - any change of month would break it) but, with the current filename formatting, all of the filenames have a numerical value of 0, so sorting them numerically doesn't do much.

use Time::Local;

my %months;
@months{('jan','feb','mar','apr','may','jun','jul','aug','sep','oct','
+nov','dec')} = 0..11;
my @lines = 
    map{ $_->[1] }
    sort{
        $a->[0] <=> $b->[0]
    }
    map{
        chomp;
        my $val = $_;
        $val =~ s#webadmin_([^\.]+)\.log#my @t=split(/_/,$1);timelocal
+(0,0,0,$t[1],$months{$t[0]},($t[2]-1900))#e;
        [$val,$_];
    }<DATA>;
print "$_\n" for(@lines);
__DATA__
webadmin_jul_10_2007.log
webadmin_jul_11_2007.log
webadmin_jul_12_2007.log
webadmin_jul_13_2007.log
webadmin_jul_14_2007.log
webadmin_jul_7_2007.log
webadmin_jul_8_2007.log
webadmin_jul_9_2007.log
[download]

webadmin_jul_7_2007.log
webadmin_jul_8_2007.log
webadmin_jul_9_2007.log
webadmin_jul_10_2007.log
webadmin_jul_11_2007.log
webadmin_jul_12_2007.log
webadmin_jul_13_2007.log
webadmin_jul_14_2007.log
[download]

I agree with your suggestion to use a ST but my preference would be to use a regex to pull out the month, day and year elements and do a three-way sort, greping only those filenames that match.

use strict;
use warnings;

my %months;
@months{qw{
   jan feb mar apr may jun jul aug sep oct nov dec}} =
   0 .. 11;

my $rxWanted;
{
    local $" = q{|};
    $rxWanted = qr
       {(?x)
           \A
           webadmin
           _(@{ [ keys %months ] })
           _(\d\d?)
           _(\d{4})
           \.log
           \z
       };
}

print
   map  { qq{$_->[0]\n} }
   sort {
            $a->[3] <=> $b->[3]
            ||
            $months{$a->[1]} <=> $months{$b->[1]}
            ||
            $a->[2] <=> $b->[2]
        }
   grep { defined $_->[1] }
   map  { chomp; [ $_, m{$rxWanted} ] }
   <DATA>;

__END__
.
..
webadmin_jul_10_2007.log
webadmin_jul_11_2007.log
webadmin_jul_12_2007.log
webadmin_jul_13_2007.log
webadmin_jul_14_2007.log
webadmin_jul_7_2007.log
webadmin_jul_8_2007.log
webadmin_jul_9_2007.log
user.log
[download]

The output is as yours.

Cheers,

JohnGG