#!perl

while (<DATA>)
{
  chomp;
  print "for [$_]:\n";
  # split on XX, but only when it's not in
  # single quotes.
  while (m% ([^']*?         # Some unquoted stuff
             (?:'[^']*'     # optionally, quoted followed by 
                 [^']*?)*? )# unquoted stuff.  non-greedy
           XX |             # field separator, or
            (.+) %xg)       #   a non-blank final field
  {
    # field value should now be in defined($2)?$2:$1
    my ($t1, $t2) = qw(undef undef);
    $t1 = "[$1]" if defined($1);
    $t2 = "[$2]" if defined($2);
    print "\t$t1\t$t2\n";
  }
}
__END__
aXXbXXc
abcd
a little 'quote XX' quote stuff XX other