#!/usr/bin/perl -w 
use strict;
use warnings;
sub main
{
    my $path = "\\\\127.0.0.1\\c$\\bak\\";
    $path =~ s/\\$//;
    print __FILE__.__LINE__." path $path\n";
    return;

}

main();



##</code><code>##

$ ./hackslash.pl
Use of uninitialized value $\ in concatenation (.) or string at ./hackslash.pl line 6.
./hackslash.pl8 path \\127.0.0.1\ak


##</code><code>##

# note the backslash in front of the dollar sign
my $path = "\\\\127.0.0.1\\c\$\\bak\\";

##</code><code>##

$ ./hackslash.pl 
./hackslash.pl8 path \\127.0.0.1\c$\bak