#!/usr/bin/perl
use warnings;
use strict;
my @data;
my $columns   = 5;
open(FH,"<BLUBBER.txt") or die $!;               
while(my $line = <FH>) {               
  chomp $line;               
my @array = (split(/[\t\s\\]/,$line))[0..($columns-1)];  
  foreach (@array) {
      s/^\s+/;/g;                    
      s/\s+$/;/g;           
  } # foreach
if ($line =~/\bBLUBB|SAND?\b/ and $line !~/\bMUSCHEL\b/){
  push(@data,[@array]);
} # if
} # while
close (FH);
my $format = '';
for my $i(0..scalar(@{$data[0]})-1){        
  my $max = find_longest(map{$_->[$i]}@data);
  $format .= '%-'.$max.'s ';
} 
for my $entry(@data){
  print sprintf($format . "\n",@$entry);
}
    open(OUTDATEN,">ZIEL.txt") or die $!;
   for my $entry(@data)
{
print OUTDATEN join(';',@$entry),"50","\n";
}
close (OUTDATEN) or die $!;
sub find_longest{                           
  my $longest = 0;
  for(@_){
      my $length = length($_);
      $longest = $length if($length > $longest);
  }
return $longest;
}  

for my $line ( @data ) {
    $line->[-1] /= 1024;
}

"my" variable $entry masks earlier declaration in same scope at BLUBBER.pl line 42.
syntax error at BLUBBER.pl line 16, near "/="
Execution of BLUBBER.pl aborted due to compilation errors

   my @array = (split(/[\t\s\\]/,$line))[0..($columns-1)];
   $array[-1] /= 1024;

$line->[-1] /= 1024;

use strict;
use warnings;
use Data::Dumper;

my @vfile = (
   's1 s2 s3 s4 32 056 KB',
   's1 s2 s3 s4 32 KB',
);

my $columns = 5;

while (defined (my $line = shift @vfile)) {
   # $columns ohne -1
   my @array = (split(/[\t\s\\]/,$line))[0..($columns)];
   # falls die 6. Spalte leer ist und kein KB da steht
   if ($array[$columns]) {
      my $last = pop @array;
      $array[-1] .= $last if $last =~ /^\d+$/;
   }
   $array[-1] = sprintf('%.2f', $array[-1] / 1024);
   foreach (@array) {
      s/^\s+/;/g;
      s/\s+$/;/g;
   }
   print Dumper(\@array);
}