[TUHS] 4.1c bsd ptrace man entry ("ptrace is unique and arcane")

[Noel Hunt]

I thought there was a filesystem in Ninth Edition called
'/tbl' wherein various system related items could be read.
I have never seen it in operation but I'm sure I saw it
in the kernel code; it seemed to fulfill all the functions
of the non-process related information that Linux dumps
into /proc.

Am I perhaps mistaken about this?


On Wed, Jun 26, 2019 at 11:13 AM George Michaelson <ggm at algebras.org> wrote:

> The lack of consistency in what you can READ in /proc makes it hard to
> believe its useful in the "wide" -but I am sure specific things get
> benefit from it, as an abstraction which makes code simple because
> "its a file"
>
> if you're WRITING into things in /proc, I think you own the pain be it
> an ioctl() or anything else.
>
> I see occasional shell scripts about turning on and off meta-state for
> SCSI or SAS as "cat 0 >
> /dev/somedir/some-model-of-abstraction/some-disk" and while I applaud,
> I also wince. So easy to go wrong..
>
> As a long-term user and non-developer, I'm sort of half a believer,
> half not. Maybe if it had emerged before the great Schism(s) it would
> be more normal? sane? understandable?
>
> -G
>
> On Wed, Jun 26, 2019 at 11:04 AM ron minnich <rminnich at gmail.com> wrote:
> >
> > On Tue, Jun 25, 2019 at 5:46 PM Larry McVoy <lm at mcvoy.com> wrote:
> > >
> > > I'm curious what Rob and others think of the Linux /proc.  It's string
> > > based and it seems like it is more like /whatever_you_might_want.
> >
> > it's very handy but quite difficult to work with programatically. The
> > output is convenient for humans to parse, not very nice for programs
> > to parse.
> >
> > /proc on linux has no real standard way of outputting things. You get
> > tables, tuples, and lists and some stuff I can't classify
> > (/proc/execdomains, /proc/devices); and, in some cases, some files
> > give you more than one type of thing. Units are not clear for many
> > tables.
> >
> > /proc on linux has far more than just process information, including
> > stuff that has nothing to do with processes (51 things on my current
> > linux, e.g. /proc/mounts).
> >
> > Things are in many cases not self-describing, though lots of /proc
> > have this issue.
> >
> > I do recall (possibly wrongly) at some point in the 2000s there was an
> > effort to stop putting stuff in /proc, but rather in /sys, but that
> > seems to have not worked out. /proc is just too convenient a place,
> > and by convention, lots of stuff lands there.
> >
> > While I was at LANL we did experiment with having /proc come out as
> > s-expressions, which were nicely self describing, composable, easily
> > parsed and operated on, and almost universally disliked b/c humans
> > don't read s-expressions that easily. So that ended.
> >
> > We've been reimplementing Unix commands in Go for about 8 years now
> > and dealing with all the variance in /proc on linux was a headache.
> > You pretty much need a different function for every file in /proc.
> >
> > And all that said, it's handy, so hard to complain about too much.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://minnie.tuhs.org/pipermail/tuhs/attachments/20190626/36767bfe/attachment.html>