This little program can do the conversion:

#!/usr/bin/perl
use warnings;
use strict;

my $rgb = shift;
$rgb = oct($rgb);
my $first = ( $rgb & 0xff0000 ) >> 16;
my $second = ( $rgb & 0x00ff00 ) >> 8;
my $third = ( $rgb & 0x0000ff );
print " ( $first , $second , $third )";
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And the output is:

C:\Code>perl rgbshift.pl 0xff00ff
 ( 255 , 0 , 255 )
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