UNTESTED, but a lot of my stuff works without testing.... :-)

my $start = "/*";
my $end = "*/";
my $inside = 0;
my $oldpos = 0;
$_ = "your text /* goes here */ and here";
while (/(\Q$start\E|\Q$end\E)/g) {
  if ($1 eq $start) {
    if (++$inside == 1) {
      $oldpos = pos($_) - length($start);
    }
  } else {
    if (--$inside == 0) {
      print substr($_, $oldpos, pos()-$oldpos);
    }
  }
}