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Bye CUPS: Printing with Netcat

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Re: Bye CUPS: Printing with Netcat

#111

Post by TylerE »

jim-jim-jim wrote: post #8

Hah. I had a similar moment of enlightenment with FreeBSD when somebody explained that you can just cat a wav file into /dev/audio (or /dev/dsp? forget the exact name). And that you can produce white noise by catting /dev/random to the same destination. With no barrier to the sound card like that, I was free to experiment with programming dfferent noise algorithms and figuring out how digital audio works. I eventuall…

I remember back in the day when I had some old HP behemoth my dad's office was throwing out... a 4100 or something like that.

I never bothered with a printing system.. I'd just cat a ps file to /dev/lp0

Re: Bye CUPS: Printing with Netcat

#112

Post by jeffreygoesto »

kindall wrote: post #32
na85 wrote: post #29

Earlier quoted context omitted.

How did you add network cards? Do some printers have PCI expansion slots?

Proprietary, not PCI, but expansion slots, yes. On HPs it was called the MIO slot and later the EIO slot. If your printer came with a MIO card that only did serial and parallel, you could swap it for one that added networking.

And if it stops working, try re-soldering it in an oven before throwing away. Some infamous batches had bad soldering problems that can be fixed. See i.e. [0]

[0] https://community.spiceworks.com/how_to/2077-how-to-bake-an-...

Re: Bye CUPS: Printing with Netcat

#113

Post by abhgh »

corbet wrote: post #21

FWIW, the Internet Printing Protocol (and IPP Everywhere in particular) make printer setup in CUPS far, far easier, but distributors seem reluctant to encourage it. I wrote about my experiences with IPP back in June ( https://lwn.net/Articles/857502/ ). I expect to never have to hassle with printer drivers again...

I read your article and finally got my Brother printer working on elementary OS! Thank you!

Re: Bye CUPS: Printing with Netcat

#114

Post by UberGuidoZ »

henearkr wrote: post #108

I immediately tried it... Aaand this is how I made my printer spit out dozens of garbage pages with just one to two lines of gibberish on each (the PDF source code, admirably giving up the page at each occurrence of the corresponding char)...

Turns out that's the same result on Windows when using Ncat /shrug

Re: Bye CUPS: Printing with Netcat

#115

Post by dredmorbius »

PaulDavisThe1st wrote: post #82
cogman10 wrote: post #27

Earlier quoted context omitted.

The secret of *nix that people don't like accepting is the file approach is often the right approach. Consider lowly embedded linux. You COULD dig down deep into the documentation of which register, which interrupt, which special memory address needs to be written to interact with the right ports on a embedded linux board. All while adding a bunch of safeguards and checks to make sure "Only you are doing this". Or, a…

The file approach ignores anything that exists (at least in part) in the time domain. Audio files are (for me) the canonical example. A text file has no inherent bit-rate. An audio file being handled without knowledge of (even just) its sample rate has its semantics distorted or destroyed. There's an awful lot of things you can do with the file approach, and I love it. Cross into the time domain and try to retain the…

Many character devices do in fact have a bitrate.

Re: Bye CUPS: Printing with Netcat

#116

Post by kelnos »

int_19h wrote: post #55
jim-jim-jim wrote: post #8

Hah. I had a similar moment of enlightenment with FreeBSD when somebody explained that you can just cat a wav file into /dev/audio (or /dev/dsp? forget the exact name). And that you can produce white noise by catting /dev/random to the same destination. With no barrier to the sound card like that, I was free to experiment with programming dfferent noise algorithms and figuring out how digital audio works. I eventuall…

I remember back when ALSA was a hot new thing on Linux, and it kinda sorta solved the "only one app can play things at the same time" problem that existed with the traditional OSS. Meanwhile, OSS on FreeBSD just worked.

It didn't, though, initially. On hardware that supported multiple streams, it worked (assuming the driver for that hardware knew how to do it), but for hardware that didn't, you had to use the ALSA dmix plugin, which for the longest time wasn't enabled by default because it was the cause of some audio artifacts.

Re: Bye CUPS: Printing with Netcat

#117

Post by Cloudef »

I wrote once a escpos emulator[1] that takes in escpos code and turns it into a bitmap image. I failed to get this bitmap image to print properly with cups so I ended up writing my own printing routines as well for that certain receipt printer[2].

1: https://git.cloudef.pw/escpos2raster.git/tree/ 2: https://git.cloudef.pw/escpos2raster.git/tree/src/bin/starpb...

Re: Bye CUPS: Printing with Netcat

#118

Post by tonyedgecombe »

jcrawfordor wrote: post #97

While the article is correct, it omits most of the actual function of CUPS. Many printers are capable of accepting various types of documents directly over the network, with postscript, HP PCL, and PDF being commonly supported---and ASCII pretty much universally supported. The problem is that few printers support _all_ of these standards. Postscript, for example, is surprisingly complex to implement in practice, whic…

I suppose if you have a printer that doesn't support PostScript or PDF then you could pipe the output through GhostScript. This is what CUPS is relying on anyway.
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