015 is "octal", and \ is escape so , octal escape, so octal escape -> Re: syntax of Data::Dump (perlquote oct octal escape perlrebackslash) -> oct

$dec_perms = (stat("filename"))[2] & 07777;
$oct_perm_str = sprintf "%o", $perms;
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So there it is

$ perl -le" print sprintf q{\\%03o}, ord $_ for qq{\r}, qq{\n} "
\015
\012

$ perl -le " $_ = qq{\r\n\r\n}; s{(.)}{sprintf q{\\%03o}, ord $1}gse; 
+print; "
\015\012\015\012
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