$ perl -MFile::Spec -le " print File::Spec->rel2abs( shift ) " tmp\tmpblah\done.pl
D:\tmp\tmpblah\done.pl

$ perl -MPath::Class -le " print file( shift )->resolve " tmp\tmpblah\done.pl
tmp\tmpblah\done.pl

$ perl -MPath::Class -le " print file( shift )->resolve->absolute " tmp\tmpblah\done.pl
D:\tmp\tmpblah\done.pl