The Unix Heritage Society mailing list
 help / color / mirror / Atom feed
From: Marc Donner <marc.donner@gmail.com>
To: Skip Tavakkolian <fariborz.t@gmail.com>
Cc: tuhs@tuhs.org
Subject: [TUHS] Re: Be there a "remote diff" utility?
Date: Thu, 16 May 2024 15:51:45 -0400	[thread overview]
Message-ID: <CALQ0xCD1--+_=71g0+2yGWSXu7WLGZfR5nUQvXWE-FEAKm248g@mail.gmail.com> (raw)
In-Reply-To: <CAA1C+h2Khq01Y85qrCZ46A597JCJTM+aCAsry_S4bKMWHgeYHA@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 2684 bytes --]

If I recall correctly, there is a combination of flags to rsync that will
generate a report on a file, a set of files, or a set of directories to
tell if they are different.

I seem to recall DPK or RCT doing something clever with rsync and cksum to
get this sort of result without having to stream a lot of data across the
long-haul network back in the day.

Best,

Marc
=====
nygeek.net
mindthegapdialogs.com/home <https://www.mindthegapdialogs.com/home>


On Thu, May 16, 2024 at 2:51 PM Skip Tavakkolian <fariborz.t@gmail.com>
wrote:

> To add to Ron's post, Plan 9's cpu exports the origination's namespace to
> the destination; by convention it is mounted on /mnt/term at destination.
>
> host1% cpu -h host2
> host2% diff file2 /mnt/term/usr/me/file1
>
>
> On Thu, May 16, 2024 at 10:09 AM ron minnich <rminnich@gmail.com> wrote:
>
>> " The 9import tool allows an arbitrary file on a remote system, with the
>> capability of running the Plan 9 exportfs(4) service, to be imported into
>> the local name space. Usually file is a directory, so the complete file
>> tree under the directory is made available."
>> https://9fans.github.io/plan9port/man/man4/9import.html
>>
>> 9import host1 / /tmp/host1
>> 9import host2 /tmp/host2
>> diff /tmp/host1/a/b/c /tmp/host2/a/b/c
>> (or whatever command you want that works with files. No need for stuff
>> like 'rdiff' etc.)
>>
>> stuff you take for granted on some systems ...
>>
>> I have the plan 9 cpu command working (written in Go) and I think it's
>> time I get import working more widely, it's just too useful.
>>
>> On Thu, May 16, 2024 at 2:01 AM <arnold@skeeve.com> wrote:
>>
>>> Ralph Corderoy <ralph@inputplus.co.uk> wrote:
>>>
>>> > > Maybe
>>> > >
>>> > >     diff -u <(ssh host1 cat file1) <(ssh host2 cat file2)
>>> >
>>> > This is annoyingly noisy if the remote SSH server has sshd_config(5)'s
>>> > ‘Banner’ set which spews the contents of a file before authentication,
>>> > e.g. the pointless
>>> >
>>> > [....]
>>> >
>>> > It appears on stderr so doesn't upset the diff but does clutter.
>>>
>>> All true, I didn't think about that.
>>>
>>> > And discarding stderr is too sloppy.
>>>
>>> But the author of a personal script knows his/her remote machines
>>> and can decide if
>>>
>>>      diff -u <(ssh host1 cat file1 2>/dev/null) <(ssh host2 cat file2
>>> 2>/dev/null)
>>>
>>> is appropriate or not.
>>>
>>> My main point was that the problem is easily solved with a
>>> few lines of shell, so no need for a utility, especially one
>>> written in C or some other compiled language.
>>>
>>> Thanks,
>>>
>>> Arnold
>>>
>>

[-- Attachment #2: Type: text/html, Size: 4390 bytes --]

  reply	other threads:[~2024-05-16 19:52 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-16  6:34 [TUHS] " Dave Horsfall
2024-05-16  6:51 ` [TUHS] " arnold
2024-05-16  7:33   ` Ralph Corderoy
2024-05-16  8:59     ` George Michaelson
2024-05-16  9:01     ` arnold
2024-05-16 17:08       ` ron minnich
2024-05-16 18:51         ` Skip Tavakkolian
2024-05-16 19:51           ` Marc Donner [this message]
2024-05-16 19:53 ` Theodore Ts'o
2024-06-19 23:20   ` Alan D. Salewski
2024-05-16 12:31 Douglas McIlroy
2024-05-16 17:12 ` Bakul Shah via TUHS
2024-05-16 18:12   ` Rich Salz
2024-05-16 18:38     ` Ben Greenfield via TUHS

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CALQ0xCD1--+_=71g0+2yGWSXu7WLGZfR5nUQvXWE-FEAKm248g@mail.gmail.com' \
    --to=marc.donner@gmail.com \
    --cc=fariborz.t@gmail.com \
    --cc=tuhs@tuhs.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).