Perl regular expression set the date

           case "2"
            {
                    setthedate();
                    break;
            }
            case "3"
            {
                    setthetime();
                    break;



sub setthedate()
{
  print( "Current system date: " );
  systemcommand( "/bin/date" , "+%Y%m%d" );
  print( "\n" );
  print( "Enter the new date (same format as above or control + c to quit)\n" );

  chomp( $input = <STDIN> ) ;
  if( $input =~ m/\d+/ )
  {  print "Setting the system date to $input ...\n";
     systemcommand( "/bin/date" , "+%Y%m%d -s $input" );
  }
  else
  {
    print "Input Error.  Please use the format from the example. System date not changed.";
  }

} # end setthedate


sub checkip(;$)
{
  if($_[0] =~ m/^(?!0+\.0+\.0+\.0)
                ([01]?\d\d?|2[0-4]\d|25[0-5])
                \.([01]?\d\d?|2[0-4]\d|25[0-5])
                \.([01]?\d\d?|2[0-4]\d|25[0-5])
                \.([01]?\d\d?|2[0-4]\d|25[0-5])$/x )
  {
    return 1;
  }
  return 0;
}
# end checkip


# regex isn't quite right but date has built in param checks
sub setthetime()
{
  print( "Current system time: " );
  systemcommand( "/bin/date" , "+%T" );
  print( "\n" );
  print( "Enter the new time (same format as above, HH:MM:SS or control + c to quit)\n" );

  chomp( $input = <STDIN> ) ;
  if( $input =~ m/([0-2]?[0-4]?\:\d+)/ )
  {  print "Setting the system time to $input ...\n";
     systemcommand( "/bin/date" , "+%T -s $input" );
  }
  else
  {
    print "Input Error.  Please use the format from the example. System time not changed.";
  }

} # end setthetime


sub menu
{
    systemcommand( "/bin/date" , "+%Y-%m-%d_%T" );

        print "\n= Appliance = \n\n ";
        print " Please enter selection: \n\n";
        print " 1. Setup IP address (requires reboot) \n";
        print " 2. Set the Date \n";
        print " 3. Set the Time \n";
        print " 4. Synchronize Time with NTP \n";
        print " 5. Modify Firewall \n";
        print "\n\n";
        print " 9. Display Network configuration \n";
        print " 0. Reboot machine \n\n";
        print ": ";
}
#end menu