Hi, I am practice perl program write a program that works like mv, renaming the first command-line argument to second command-line argument considering to handle destination is a directory: 
($old, $new) = @ARGV;
if (-d $new) {
    ($basename = $old) =~ s#.*/##s;  #what two s and three #mean ?
     $new .= "/$basename";
}

[download]
please help and thanks in advance!

In reply to regular express problem by Anonymous Monk

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