sub getdir
{
  my $valid=0;
  my $answer;
  my ($type,$default)=@_;
  my $blurb='Directory to install ';
  while(!$valid)
  {
    print "$blurb$type [$default]\n : ";
    chomp($answer=<STDIN>);
    $answer=$answer || $default;
    chop $answer if $answer =~ m#/$#;
    if(chdir $answer){$valid=1;}
    else{print "Can't access directory \"$answer\". Try again\n";}
  }
  return $answer;
}

my $docroot=getdir('HTML files','/var/www');
my $scripts=getdir('CGI scripts','/usr/lib/cgi-bin');