Re: [PATCH] ip.7: Add not supported by SOCK_STREAM to socket options

From: Oliver Crumrine
Date: Wed Mar 06 2024 - 08:02:33 EST


On Wed, Mar 6, 2024 at 5:58 AM Alejandro Colomar <alx@xxxxxxxxxx> wrote:
>
> Hi Oliver,
>
> On Tue, Mar 05, 2024 at 02:31:48PM -0500, Oliver Crumrine wrote:
> > Hi Alex,
> > I have attached two programs in the form of C source code below. No
> > special compilation options required. To change between the three
> > different socket options outlined in my patch, there are two options on
> > line 16 and 18 with a comment above them explaining how to use the
> > fields.
> >
> > Here's how to use the programs:
> > 0. Make sure you have netcat installed.
> > 1. Compile the dgram one.
> > 2. Run it.
> > 3. Run nc localhost 8888 -u (in a seperate terminal window or tab)
> > 4. Type whatever into netcat and press enter
> > 5. Observe that there is a control message recieved, and there is a byte
> > printed, which is the first byte of the data in the control message.
>
> Can't reproduce this. The terminal running nc(1) isn't printing
> anything.
>
> alx@debian:~$ which nc
> /usr/bin/nc
> alx@debian:~$ which nc | xargs realpath
> /usr/bin/nc.openbsd
> alx@debian:~$ dpkg -S /bin/nc.openbsd
> netcat-openbsd: /bin/nc.openbsd
>
> > 6. You may repeat this for the three different socket options.
> > 7. Repeat for the stream one, but use nc localhost 8888 (without the -u)
> > for #5.
> > 8. Observe that there are no control messages recieved with the stream one,
> > and byte is 00, which is the initial value of the variable, before it has
> > a value assigned when the control messages (of which there are none) are read.
> >
> > Thanks,
> > Oliver
>
> Have a lovely day!
> Alex
>
Hi Alex,
Type into netcat, not the program I sent.
My program is the server and prints out whatever it recieves,
along with some other stuff that lets you know which options
are supported.
Thanks,
Oliver