Hi Manfred,
Did you see/study the example/test UDPSocketEchoTest ?
Also, UDP is very primitive: it is send and forget, returns no errors, and is
totally asynchronous. Listening should best be done in a separate process.
Here is how I would write your send part:
| message udpSocket |
message := String crlf join: #(
'M-SEARCH * HTTP/1.1'
'HOST:239.255.255.250:1900'
'MAN:"ssdp:discover'
'ST:ssdp:all'
'MX:1'
'').
udpSocket := Socket newUDP.
udpSocket sendData: message toHost: #[239 255 255 250] port: 1900.
udpSocket waitForSendDoneFor: 5.
udpSocket closeAndDestroy.
Maybe nothing came back because the line ends where wrong ?
HTH,
Sven
> On 18 May 2015, at 11:29, Manfred Kröhnert <mkroehner...@googlemail.com>
> wrote:
>
> Hello everyone,
>
> I am currently trying to get a list of UPnP device via SSDP (Simple Service
> Discovery Protocol).
>
> A minimalistic working NodeJS example looks like this:
>
> var dgram = require('dgram');
> var message = new Buffer(
> "M-SEARCH * HTTP/1.1\r\n" +
> "HOST:239.255.255.250:1900\r\n" +
> "MAN:\"ssdp:discover\"\r\n" +
> "ST:ssdp:all\r\n" +
> "MX:1\r\n" +
> "\r\n"
> );
>
> var client = dgram.createSocket("udp4");
>
> client.on("message", function (msg, rinfo) {
> console.log("server got: " + msg + " from " + rinfo.address + ":" +
> rinfo.port);
> });
> client.send(message, 0, message.length, 1900, "239.255.255.250");
> client.close();
>
> I tried to recreate the same functionality in Pharo with the following piece
> of code:
>
> | message udpSocket host |
> message := 'M-SEARCH * HTTP/1.1\r\n' ,
> 'HOST:239.255.255.250:1900\r\n' ,
> 'MAN:"ssdp:discover"\r\n' ,
> 'ST:ssdp:all\r\n' ,
> 'MX:1\r\n' , '\r\n'.
>
> udpSocket := Socket newUDP.
> host := (NetNameResolver addressFromString: '239.255.255.250').
> udpSocket sendData: message toHost: host port: 1900.
> "udpSocket waitForData."
> Transcript show: 'Received: ' , udpSocket receiveData.
> udpSocket closeAndDestroy.
>
> Unfortunately, this script hangs both in Pharo3 and Pharo4 (OS X 10.10, Pharo
> 30856 and 40611).
> When I interrupt with Cmd+. the debugger shows the method
> Socket>>waitForDataIfClosed:
> and the hang is apparently in the line
> self readSemaphore wait
>
> Could anyone give me some advice if I should to do this differently or what
> the issue with the Pharo script is?
>
> Thanks in advance,
> Manfred
