You can do basically the same with perl

open (INPUT, "<$flatfile");
while(<INPUT>) {
   $_ =~ /[dlrwxsS-]{10}\s/\n/g;
   print;
}
close INPUT;
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This snippet will substitute the (for example) "lrwxr-xr-x" part into a \n character. I took [dlrwxsS-] to match the possible characters. I might have forgotten one or two possibilities ;)