Because you never call the main subroutine. 
use strict;
use warnings;
sub main
{
    my $path = "\\\\127.0.0.1\\c\$\\bak\\";
    $path =~ s/\\$//;
    print __FILE__.__LINE__." path $path\n";
    return;

}
main();

[download]
or even better 
use strict;
use warnings;

my $path = <<'EOT';
\\127.0.0.1\c$\bak\
EOT
$path =~ s/\\$//;
printf "%s %s path %s\n", __FILE__, __LINE__, $path;

[download]

Unlike C or Java, you don't need a main subroutine; the script just runs in the order it's written, like a shell script. Note as well that I had to escape your $ since " interpolates - you were inserting $\ into your $path assignment. If you'd actually run your subroutine, you would have gotten a warning.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Why I can't remove trailing slash by kennethk
in thread Why I can't remove trailing slash by anaconda_wly

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