Adding "use warnings;" at the top of your code would have told you:

Unrecognized escape \k passed through at C:\Data\Perl\Script\Perl-1.pl
+ line 6.
Unrecognized escape \k passed through at C:\Data\Perl\Script\Perl-1.pl
+ line 6.
Unrecognized escape \s passed through at C:\Data\Perl\Script\Perl-1.pl
+ line 6.
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immediately hinting to you that the \k, \k and \s are being interpolated.

To avoid this, use single quotes:

my $name = 'C:\karate\kid\sucks';
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Of course the answer still 'sucks' ;-)

This behaviour has nothing to do with the module not "understanding" what shell or OS you are using, the interpolation already happens when you assign "C:\karate\kid\sucks" to the variable. There is no way Perl can know at that moment that this string is a filepath and that it should not use \ as an escape sequence. After all by double-quoting the string you specifically indicated that you want this to be interpolated!