Re: Help on sending a UDP Packet

[address@hidden]

Also note that I set the remote address on the Datagram object.

I am not sure whether it matters, but I see in the code that you posted that 
you set the remote address on the DatagramSocket.

----- Op 12 jan 2021 om 19:50 schreef stes stes@telenet.be:

> Gary,
> 
> I cannot tell whether GNU smalltalk is stable or not,
> only whether the simple datagram daytime test works for me ...
> 
> Also it may be that GNU smalltalk has different strengths than socket
> programming,
> the fact that they have on the roadmap for GNU smalltalk 3.3 a 'complete
> rewrite'
> of the socket code, worries me to say the least ...
> 
> When I modify the script that I posted to use a different host, it works for 
> me:
> 
> First I test from a different host a connection to host 'antar' :
> 
> bash-4.4$ nc -u antar 13
> 123
> Tue Jan 12 19:41:27 2021
> ^C
> 
> Then when I do the same thing with GNU smalltalk 3.2.5 from the remote host it
> works:
> 
> bash-4.4$ cat daytime-dgram.st
> PackageLoader fileInPackage: 'Sockets'.
> 
> h _ Sockets.SocketAddress byName:'antar'.
> h printNl.
> s _ Sockets.DatagramSocket new.
> d _ Sockets.Datagram data:#'hello world' address:h port:13.
> answer _ Sockets.Datagram new.
> s nextPut:d.
> s receive:answer.
> (answer data) asString printNl.
> s close.
> 
> bash-4.4$ gst daytime-dgram.st
> Loading package ObjectDumper
> Loading package Sockets
> 192.168.0.2
> 'Tue Jan 12 19:46:56 2021
> '
> 
> This is of course assuming that 'antar' returns the dgram daytime service.
> 
> But that in itself is a classical simple test for datagrams.
> 
> Regards,
> David Stes
> 
> ----- Op 12 jan 2021 om 17:28 schreef Gary Highberger 
> gary.highberger@gmail.com:
> 
>> Hi David and everybody,
>> 
>> I just sent my first UDP packet with Smalltalk Sockets. It's likely just me
>> but there might be some instability in gst. Somehow my Datagram Socket got
>> wiped out. I'm going to run tests and publish my findings here.
>> 
>> Have GNU Smalltalk Sockets and the VM been proven in real world
>> applications?
>> 
>> Packet:
>> $ sudo tcpdump -i 1 -nn -n -A port 49152
>> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
>> listening on wlp3s0, link-type EN10MB (Ethernet), capture size 262144 bytes
>> 10:53:15.131345 IP 192.168.1.114.49153 > 192.168.1.249.49152: UDP, length 27
>> E..7..@.@..0...r.........#..  Hi sailor! New in town?
>> 
>> Smalltalk:
>> st> PackageLoader fileInPackage: 'Sockets'
>> "Global garbage collection... done"
>> Loading package Sockets
>> PackageLoader
>> st> DgS := Sockets.DatagramSocket remote: '192.168.1.249' port: 49152
>> local: '192.168.1.114' port: 49153
>> Sockets.DatagramSocket[192.168.1.114:49153]
>> st> DgD := Sockets.Datagram data: '  Hi sailor! New in town?  '
>> a Datagram
>> st> DgS nextPut: DgD
>> Sockets.DatagramSocket[192.168.1.114:49153]
>> Voila
>> 
>> Many thanks for the help everybody!
>> 
>> Gary
>> 
>> On Sun, Jan 10, 2021 at 1:49 PM Gary Highberger <gary.highberger@gmail.com>
>> wrote:
>> 
>>> Hello David and all,
>>>
>>> I have a few (noob) questions about the UDP example Smalltalk program.
>>> More questions likely to follow as I come up to speed. Your patience is
>>> much appreciated David and everybody.
>>>
>>> QUESTIONS:
>>> •  Is "_" the preferred assignment operator? I've been seeing ":=" too. I
>>> don't have a back arrow on my keyboard. I guess the PARC people used "_".
>>>
>>> •  Does statement 1)
>>> assign the destination IP address? Note that for my application, the
>>> source and destination addresses will be different.
>>>
>>> •  Does statement 3)
>>> populate the (UDP) datagram socket with the message, port, and address?
>>> Why a "#" symbol prefixing the message string, 'hello world'?
>>>
>>> •  Does statement 4)
>>> create a listening socket?
>>>
>>> •  Does statement 5)
>>> trigger the send?
>>>
>>> •  Does statement 6)
>>> block until the UDP response?
>>>
>>> +---------------------------------------------------------+
>>>
>>> UDP Smalltalk (example) program:
>>>
>>> 1) h _ Sockets.SocketAddress createLoopbackHost.
>>>
>>> 2) s _ Sockets.DatagramSocket new.
>>>
>>> 3) d _ Sockets.Datagram data:#'hello world' address:h port:13.
>>>
>>> 4) answer _ Sockets.Datagram new.
>>>
>>> 5) s nextPut:d.
>>>
>>> 6) s receive:answer.
>>>
>>> 7) (answer data) asString printNl.
>>>
>>> 8) s close.
>>>
>>> Gary Highberger
>>>
>>>
>>> On Sun, Jan 10, 2021, 8:48 AM Gary Highberger <gary.highberger@gmail.com>
>>> wrote:
>>>
>>>> Good morning David,
>>>>
>>>> I'm not familiar with 'daytime' but will come up to speed on it and get
>>>> it and your use cases running and report my findings for everybody to see.
>>>>
>>>> Hopefully netTest.c explains what I'm trying to do with Smalltalk. It's
>>>> very short and simple.
>>>>
>>>> https://www.dropbox.com/s/xc23wj6r5aqh153/netTest.c?dl=0
>>>>
>>>> I used my cell phone as the destination, my home WiFi as the network, and
>>>> tcpdump to see the packet.
>>>>
>>>> Thank you David for the Smalltalk code fragments and introducing me to
>>>> inetd and 'daytime'.
>>>>
>>>> Gary Highberger
>>>>