Re: [racket-users] Re: Confusion with udp-receive!

2019-09-26 Thread David Storrs
On Wed, Sep 25, 2019 at 8:16 PM David Storrs wrote: > > On Wed, Sep 25, 2019 at 7:45 PM Alex Harsanyi wrote: > > > > Is there any tunneling involved for connecting to your AWS instance? > > > > There is only one copy of the source port in an IP+UDP datagram, and this > > needs to be whatever

Re: [racket-users] Re: Confusion with udp-receive!

2019-09-25 Thread Alex Harsanyi
Is there any tunneling involved for connecting to your AWS instance? There is only one copy of the source port in an IP+UDP datagram, and this needs to be whatever the router is using for NAT, otherwise it would not be able to route replies back to your machine on the local network. If you

Re: [racket-users] Re: Confusion with udp-receive!

2019-09-25 Thread David Storrs
On Wed, Sep 25, 2019 at 2:57 PM Matthew Flatt wrote: > > At Wed, 25 Sep 2019 12:49:36 -0400, David Storrs wrote: > > 1) Is it possible that there is a bug in the underlying C code? > > It's always possible. But if I understand the original problem, it > seems unlikely that a bug manages to

Re: [racket-users] Re: Confusion with udp-receive!

2019-09-25 Thread George Neuner
On 9/25/2019 2:57 PM, Matthew Flatt wrote: At Wed, 25 Sep 2019 12:49:36 -0400, David Storrs wrote: > 1) Is it possible that there is a bug in the underlying C code? It's always possible. But if I understand the original problem, it seems unlikely that a bug manages to exactly reconstruct a

Re: [racket-users] Re: Confusion with udp-receive!

2019-09-25 Thread Matthew Flatt
At Wed, 25 Sep 2019 12:49:36 -0400, David Storrs wrote: > 1) Is it possible that there is a bug in the underlying C code? It's always possible. But if I understand the original problem, it seems unlikely that a bug manages to exactly reconstruct a port number that has been replaced in a UDP

Re: [racket-users] Re: Confusion with udp-receive!

2019-09-25 Thread David Storrs
We (my business partner and I) ran tcpdump on the router and determined that no, it is not using the local port. At first it bound to 65395 and then after we stopped/started the process it bound to a different port (49428) as expected. After a bit of digging in the racket source code I note that

Re: [racket-users] Re: Confusion with udp-receive!

2019-09-25 Thread David Storrs
On Wed, Sep 25, 2019, 3:16 AM Alex Harsanyi wrote: > Do you know what port the router is using for NAT? Are you sure that the > router is not simply choosing the same port, so 25890 is both your local > port and the port used by the router? > I haven't yet 100% ruled it out, but it doesn't

[racket-users] Re: Confusion with udp-receive!

2019-09-25 Thread Alex Harsanyi
Do you know what port the router is using for NAT? Are you sure that the router is not simply choosing the same port, so 25890 is both your local port and the port used by the router? Alex. On Wednesday, September 25, 2019 at 1:08:16 PM UTC+8, David Storrs wrote: > > udp-receive! is giving me