I like a magic %! approach, say

use Errno;
sub Fudge {
  my @r;
  while( my($k,$v)=each %!){
    $v and push @r, $k
  }
  join qq/\n/,
    int($!).q/ /.$!,
    int($^E).q/ /.$^E,
    @r, q/ /
}

open my($fh),qw/ < ./ or die Fudge();
__END__
13 Permission denied
5 Access is denied
ERROR_INVALID_DATA
EMR_SETBRUSHORGEX
EACCES
  at - line 13.
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