Subject: Re: lpd and filter programs
To: Bernd Salbrechter <salb@hell.gud.siemens.at>
From: Todd Whitesel <toddpw@best.com>
List: tech-userlevel
Date: 07/23/1998 05:25:58
> I have done allready an experimental "papercap" file, with size,
> margins and rules for printing 2 pages on one sheet of paper (front and
> backside). Currently I design a higer level interface (like curses to
> termcap) to enable queries like "which margins should I use on the even
> and the odd page".  I use "roff" and "reminder" to get PostScript pages,
> which I mount with "pstools" on paper (12 pages on 2 sides of one sheet,
> fold, punch and cut and have it in the right order).

I really like hearing about research along these lines. Too many rushed
implementations exist in the commercial world, because users want them
so badly they are willing to pay big bucks for somebody else to do all
the thinking.

There is also the legwork of collecting information about all the diverse
hardware out there. It would be really cool to have a system so that when
you get a new piece of hardware, you can look out across the net for
settings that other people said worked for them, and once you find a
setting that works for you, you can send it to the database and it gets
recorded for future searches. I first thought of this while pondering all
the pain and suffering caused by disk drive geometries, but it generalizes.

> Someone (maybe NetBSD) should start to add such a database to the System,
> which can be realy usefull for many printing tools.  If there is any
> interest I like to discuse this in future, even I didn't have much time
> for this baby at the moment.

There are many services that deserve this treatment. However I would like
to advise against an automatic proliferation of new /etc files.

I feel very strongly that, in the long term, the majority of the system
installation should be mounted read-only and normally only modified by
'sysinst' or while in single-user mode. System configuration needs to be
partitioned so that non-critical devices and system options can be set up
by Lusers. A litmus test case is that unless an administrator specifically
disallows it, non-root users should be allowed to invoke 'newfs' and 'mount'
on a ZIP disk, or a USB floppy drive.

The main implication of this principle is that concepts like the split passwd
file and NIS integration should be cleaned up and then used as the basis of
a standard infrastructure. For example, fstab and the automounter could be
split into many levels (these examples are just off the top of my head ok?):
    /etc/fstab
	boot disk, swap disk, /usr, mfs on /tmp
    NIS-distributed static and auto mounts available on all machines
	/home/joeblow, /tools/egcs
    Luser-editable net-wide mounts
	/net/joeblow/mandelbrot-pictures, /net/shells/new-bash
    Luser-editable machine-wide mounts
	/cdrom, /share/our-project
    Luser-private mounts
	~/zip, ~/mnt/hollys-porno-palace

~/.etc/fstab, anyone?

Now imagine using this infrastructure to control access to printers. It's
easy for someone to plug in a USB printer and enable it in ~/.etc/printcap
so no one else sees it, or in a systemwide printcap file. Printers managed by
the IT department can be exposed to the entire network via NIS-style pushing.
Default printer aliases to the physically closest printer could be set at any
of the various levels depending on security/flexibility concerns.

Todd Whitesel
toddpw @ best.com