Re: [Pharo-users] On UDP broadcast

Hi Hilaire, Check UDPSocketEchoTest for a good, simple example of using UDP sockets in Pharo. You should not do #connectTo:port: but just #setPort: and listen. HTH, Sven

On 20 May 2018, at 20:59, Hilaire <hilaire@drgeo.eu> wrote:

Hi,

I try to figure out this matter. I am just new to this domain so excuse me for the obvious the errors.

To broadcast an IP, this seems to work:

| socket |

socket := Socket newUDP. socket setOption: 'SO_BROADCAST' value: true. 10 timesRepeat: [ socket sendUDPData: '10.7.2.1' toHost: #[255 255 255 255] port: 9999. (Delay forSeconds: 1) wait. ]. socket closeAndDestroy.

Then I can listen from the shell: with: nc -ulk 9999

Now for the listener part, I wrote something like:

| socket data | socket := Socket newUDP. socket connectTo: NetNameResolver loopBackAddress port: 9999. socket waitForConnectionFor: 2. [data := socket receiveDataTimeout: 5. data crLog] ensure: [ socket closeAndDestroy]

But I got an error when connecting the socket, the debugger message is:

"InvalidSocketStatusException: Socket status must Unconnected before opening a new connection"

So far I don't see understand this error. Port 9999 is not in use, and running again after this error the broadcast code does not lead to an error.

Any idea?

Thanks

Hilaire

-- Dr. Geo http://drgeo.eu