It's also possible to use  '*' as a quantifier to pack/unpack whatever number of the specified data type happens to be present:

c:\@Work\Perl\monks>perl -wMstrict -MData::Dump -le
"my $p = pack 'C*', (65, 66, 0x43, ord('D'), 0b01000101);
 print qq{'$p'};
 ;;
 my @u = unpack 'C*', $p;
 dd \@u;
"
'ABCDE'
[65 .. 69]
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