my @sorted = sort { property($a) <=> property($b) } @unsorted;

##</code><code>##

($foo, $bar, $baz, ...)

##</code><code>##

{ property($a) <=> property($b) }

##</code><code>##

([$foo, property($foo)], [$bar, property($bar)], [$baz, property($baz)], ... )

##</code><code>##

{ $a->[1] <=> $b->[1] }

##</code><code>##

my @st        = map  { [ $_, property($_) ] } @files;
my @sorted_st = sort { $a->[1] <=> $b->[1] }  @st;
my @sorted    = map  { $_->[0] }              @sorted_st;

sub property { ( $_[0] =~ /fwlog\.(\d+)\w+/ )[ 0 ] };

##</code><code>##

my @sorted =
  map  { $_->[0] }
  sort { $a->[1] <=> $b->[1] }
  map  { [ $_, ( $_[0] =~ /fwlog\.(\d+)\w+/ )[ 0 ] ] }
  @files;

##</code><code>##

  sort { $a->[1] <=> $b->[1] or
         $a->[2] cmp $b->[2] or
         $b->[3] <=> $a->[3] }