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

dbmopen(my %h_FileMd5Sum_PerlDB, "test.dbm", 0660 );
print "Aktuell drin:\n";
print Dumper \%h_FileMd5Sum_PerlDB;

if ($ARGV[0] && $ARGV[0] eq 'clean') {
    print "Leere Hash.\n";
    %h_FileMd5Sum_PerlDB = ();
} else {
    print "Fuege Wert hinzu.\n";
    $h_FileMd5Sum_PerlDB{rand()} = rand();
}
dbmclose %h_FileMd5Sum_PerlDB;