%input = getforminput(); # That's another thread...
if ($input{formsubmitted}==2) {
  # user submitted form2.  Process it and print a
  # "form sumbitted" advisory page.
} elsif ($input{formsubmitted==1) {
  # user submitted form1.  Process it and print form2.
} else {
  # User didn't submit anything yet.  Print form1.
}