You might be able to narrow this further, but testing for the existence of the errant file prior to each step. Try the equivalent of: 
  use File::Path;
    foreach my $n ( 0 .. 12 ) {
      print "/blah/10 exists prior to step $n\n"
        if -e "/blah/10";
      mkpath("/blah/$n", 1, 0755) or die "$n: $!";
  }

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In reply to Re: output of test script by dws
in thread freaky mkdir problem by markguy

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