I am assuming that when you say "pure perl" you mean without having to use a Perl module. In that case why not case off of the $^O (OS) variable ... you know ... something like this ... 
sub setRecursiveCopyCommand {
    my $OS = $^O; 
    
    if ( $OS eq 'VMS' ) {
       return whatever the hell they do in VMS 
    } elsif ( $OS eq 'PLAN9' ) {
       return whatever the hell they do in PLAN9
    } elsif ( $OS eq monkeys_fly_out_of_my_ass ) {
       you get the picture
    } else {
    ...
}

[download]
Note above code is untested. And may require some effort on your part ... :P

Plankton: 1% Evil, 99% Hot Gas.

In reply to Re: Copying a directory recursively by Plankton
in thread Copying a directory recursively by BUU

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