If the entire string (after the first 'no of strings' byte) is made up length/string pairs, then (subject to using an unenbalmed version of Perl) let unpack take care of it. Ignore/skip the first byte and use the ()repeat pattern to deal with it. Eg:

$count = 3;
$str1 = "First string";
$str2 = "Second string";
$str3 = "Third string";
$bytes = pack("C C A* C A* C A*", $count, length($str1),
   $str1, length($str2), $str2, length($str3), $str3);;

print for unpack 'x(c/a*)*', $bytes;;
First string
Second string
Third string
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If there is other stuff following the strings, then you'll need to unpack the first byte and then generate the pattern:

$n = unpack 'C', $bytes;;

print for unpack 'x (c/a*)' . $n, $bytes;;
First string
Second string
Third string
[download]