I want to sort the output from du -sh, from the big size to small size, here is an example 

33G     /data/A
37M     /data/B
44G     /data/C
46G     /data/D
68G     /data/E
114G    /data/F
148G    /data/G
169M    /data/H

[download]

her is my test code

my $file_dist="../data/disk_usage.dat.new.bkp";
##open the usage file
open(my $fh ,$file_dist) or die "can not open file";

my @arr = ();
my @sorted = ();

while(my $line=<$fh>){
    chomp $line;
    push(@arr, $line);
}

@sorted = sort sort_arr @arr;
print Dumper \@sorted;

sub sort_arr {
      my ($size_a, $type_a);
      if($a =~ /(\d*?\.*\d*)([M|G|K])/){
         $size_a = $1;
         $type_a = $2;
      }
            
      my ($type_b, $size_b);
      if($b =~ /(\d*?\.*\d*)([M|G|K])/){
         $size_b = $1;
             $type_b = $2;
      }
            
      my $a1 = return_base($type_a) * $size_a;
      my $b1 = return_base($type_b) * $size_b;

      $b1 <=> $a1 ;            
}    

sub return_base{
    my $type = shift;    
    return 1024 if ($type eq "M");
    return 1024*1024 if($type  eq "G");
    return 1 if($type  eq "K");
}

sub trim{
    my $s=shift;
    $s=~s/\s+$//;
    $s=~s/^\s+//;
    return $s;
}

[download]

My question is why in sub sort_arr, I don't need to use defination, like my $a, my $b?

In reply to sort file with your own logic by citi2015

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