Problem with UNPACK

[Tin-Shan Chau]

I have run into the following problem: If I concatenate the packed values of a list to 
a string, when I use the unpack operation to put the values back into an array, the 
last element is missing.  I can only get around the problem by specifying the exact 
number of elements to unpack.  And if I don't have that available, I would have to do 
two unpack operations, the first one to find out how many elements are in the array of 
packed values, the second to get the last value.  This seems rather a waste to me.  Is 
there any way to solve this problem.  Your help would be greatly appreciated.  Thanks 
in advance.


The following program illustrates the problem I am having:
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
$TBLXCOL_FORMAT = 'I/a*';
$lines[0] = "CLASSCOUNT         PSOPRDEFN               8     2 SMALLINT N";
$lines[1] = "OPERPSWD           PSOPRDEFN               9    32 CHAR     N";
$lines[2] = "ENCRYPTED          PSOPRDEFN              10     2 SMALLINT N";
$lines[3] = "SYMBOLICID         PSOPRDEFN              11     8 CHAR     N";
for ($i=0;$i<4;$i++) {
   ($column, $table) = split / +/, $lines[$i];
   if (!exists($tblxcol{uc($table)})) {
      $tblxcol{uc($table)} = pack ($TBLXCOL_FORMAT, $column);
   }
   else {
      $tblxcol{uc($table)} .= pack ($TBLXCOL_FORMAT, $column);
   }
}
print "1st example\n";
@array = unpack $TBLXCOL_FORMAT x 500, $tblxcol{PSOPRDEFN};
printf ("Array size: %ld\n", $#array+1);
$i = 0;
foreach $item (@array) {
   $i++;
   print "$i   $item\n";
}
print "\n2nd example\n";
@array = unpack $TBLXCOL_FORMAT x ($#array+1), $tblxcol{PSOPRDEFN};
$i = 0;
foreach $item (@array) {
   $i++;
   print "$i   $item\n";
}
exit 0;