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Re: BUG or OPERATOR error? - was [Re: Measuring aggregate internet useage?]



On Mon, May 01, 2017 at 01:18:58PM -0500, David Wright wrote:
> They do. Both expect a command. You can "show" something but you can't
> "dev" it or, at least, I don't know how to.

The surprise comes from the fact that typically you can add "dev eth0"
to the end of one working ip command, to get another working ip command
which is restricted to that one interface -- but not always.

ip addr show (working)
ip addr show dev eth0 (working)

But

ip addr (working)
ip addr dev eth0 (NOT working)

And

ip -s link show (working)
ip -s link show dev eth0 (working)

But

ip -s link (working)
ip -s link dev eth0 (NOT working)

Apparently, in order to understand why half of the commands work and
half do not, you have to somehow figure out that you're currently using
a command with an assumed verb, and that this makes a difference, in
some way, if you try to add words that follow the assumed verb.  Like,
"the verb is only added if the parser runs out of words" or something.

The inconsistency is quite confusing, especially if you haven't
scientifically attempted EVERY combination of words yet, to see which
combinations work and which do not, in order to analyze it for patterns
and infer the actual grammar rules.


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