[cups] programmatically detect network printer power state

[Brian Potkin]

On Thu 02 Jun 2016 at 09:46:31 +0200, Johannes Meixner wrote:

> On Jun 1 19:07 Brian Potkin wrote (excerpt):
> >
> >I think CUPS reports the state of the print queue.
> 
> "printer" =~ "printer device" != "print queue" =~ "printer"
> 
> Cf. "CUPS: The server between user and printer" at
> https://en.opensuse.org/Concepts_printing
> 
> To avoid possile misunderstandings that might lead to
> possibly endless talking at cross purposes I recommend
> to keep printers (i.e. printer devices) and print queues
> strictly separated and accordingly I recommend to use
> unambiguous wording to keep "printer devices" obviously
> separated from "print queues".

In many cases no confusion arises but I'd agree with that.

[...snip...]

> In general to get the state of a network printer device
> you can usually use SNMP.

I have an ancient JetDirect print server with three parallel ports. The
snmp backend does not detect it. I keep thinking that one day I'll
investigate and find out why.
 
> It depends what exactly "on or off" means.

John Boncek might get a simpler, more suitable solution if he said why
he wanted to detect the on/off state of the printer and what he would do
with the information.

Regards,

Brian.