Perl 5 version 8.7 documentation
oct
- oct EXPR
- oct
Interprets EXPR as an octal string and returns the corresponding value. (If EXPR happens to start off with
0x
, interprets it as a hex string. If EXPR starts off with0b
, it is interpreted as a binary string. Leading whitespace is ignored in all three cases.) The following will handle decimal, binary, octal, and hex in the standard Perl or C notation:- $val = oct($val) if $val =~ /^0/;
If EXPR is omitted, uses
$_
. To go the other way (produce a number in octal), use sprintf() or printf():The oct() function is commonly used when a string such as
644
needs to be converted into a file mode, for example. (Although perl will automatically convert strings into numbers as needed, this automatic conversion assumes base 10.)