This is a very primitive yet complete example of a telnet server written in RunRev. You can access it from the unix terminal with the command

telnet localhost 2222

It might work from the Windows command line as well, although you may have to replace “cr” with “numToChar(13) in the script below –just give it a try. After connecting, type something in the terminal and see what happens. Type “close” to close the connection.

In RunRev, all you need is to create a button with the script below. Set the label of the button to “Start” or click the button twice when you run the server for the very first time.

on mouseUp
     if the label of me is not “Start” then
          closeAllSockets
          set the label of me to “Start”
     else
          accept connections on port 2222 with message “welcome”
          put the result into rslt
          if rslt is not empty then
               beep
               answer error rslt
          else
               set the label of me to “Stop”
          end if
     end if
end mouseUp

on welcome theSock,thePort
     write “Welcome. You are connected.” & cr & “rev> ” to socket theSock
     read from socket theSock until cr with message “telnet”
end welcome

on telnet theSock,theMsg
     // uncomment next line if you want to see the message in a field
     // put theMsg into fld 1
     if theMsg begins with “close” then
          write “byebye” & cr to socket theSock
          close socket theSock
     else
          if theMsg begins with “beep” then beep
          write “You wrote:” && theMsg & “rev> ” to socket theSock
          read from socket theSock until cr with message “telnet”
     end if
end telnet

on closeAllSockets
     put the openSockets into mySocks
     repeat for each line mySock in mySocks
          close socket mySock
     end repeat
end closeAllSockets