oct
oct - convert a string to an octal number
oct EXPR
Interprets EXPR as an octal string and returns the corresponding
decimal value. (If EXPR happens to start off with 0x, interprets it as
a hex string instead.) The following will handle decimal, octal, and
hex in the standard Perl or C notation:
$val = oct($val) if $val =~ /^0/;
If EXPR is omitted, uses
$_
.