#!/bin/perl

use strict;
use warnings;

my $sharename='c$';

my $filename1='\\\\dual\c$\test dir\Neu Textdokument.txt';
my $filename2='\\\\dual\\c$\\test dir\\Neu Textdokument.txt';
my $filename3="\\\\dual\\c\$\\test dir\\Neu Textdokument.txt";
my $filename4="\\\\dual/c\$/test dir/Neu Textdokument.txt";
my $filename5="//dual/c\$/test dir/Neu Textdokument.txt";
my $filename6="//dual/$sharename/test dir/Neu Textdokument.txt";

my $testfile=$filename6;

# Test1
system($testfile);

# Test2
  if (open FH,'<',$testfile) {
    while(<FH>) {
      print;
    }
    close (FH);
  }
  else {
    print "$!\n";
  }