Standardise port names for NIC type apps

[plajjan]

I think it would make sense to standardise the port names for NIC type apps. Intel app calls it rx/tx where Tap uses input/output. In general I think it would be useful if we could adhere to a uniform standard for simple apps (where there is only input/output).

Personally I would prefer to rename the Intel ports to input/output. This was one of the first things I ran into with Snabb when I started playing with it 2 years ago. Somewhat embarrassingly I put myself in the same position just last week and it took me way to long to notice that I was using the wrong port names.

Having the same names would make it easier to write apps that can easily switch between multiple types of NICs.

[lukego]

Yes! Consistent naming has been on my list forever too. I agree that input and output are better names than rx and tx too.

The only alternative I see worth considering is anonymous ports accessed by index. Then the name is irrelevant. This is already implemented but I know that you recently noticed problems with the implementation (can't distinguish between the first port or a port named 1) so I would be okay with removing that anonymous-ports feature and always using names instead.

[eugeneia]

I want to make this change because it enables the “common I/O” API we need. So, are we set on input/output over rx/tx? The statistics framework currently uses {rx,tx}{bytes,packets,errors,...} as standard names, should these be changed to {input,ouput}{bytes,packets,errors,...} accordingly?

[petebristow]

I would certainly prefer input / output.
Yes I think all references to rx/tx should become input / output.

[eugeneia]

I opened #1025 to resolve this issue. Help is welcome!