c:\test>perl -le"
my $n = oct( $ARGV[ 0 ] ); 
printf qq[As decimal: %d As octal: %o \n], $n, $n; 
" 0644

As decimal: 420 As octal: 644

##</code><code>##

c:\test>perl -le"my $n = oct( $ARGV[ 0 ] ); print 'As a string:' . $n; " 0644
As a string:420


##</code><code>##

c:\test>perl -le"my $n = oct( $ARGV[ 0 ] ); print 1 + $n; " 0644
421