Re: Contents of file changed while application is reading it

Path	csiph.com!weretis.net!feeder6.news.weretis.net!news.misty.com!border-2.nntp.ord.giganews.com!nntp.giganews.com!Xl.tags.giganews.com!local-1.nntp.ord.giganews.com!nntp.earthlink.com!news.earthlink.com.POSTED!not-for-mail
NNTP-Posting-Date	Wed, 01 Mar 2023 06:33:00 +0000
Subject	Re: Contents of file changed while application is reading it
Newsgroups	comp.os.linux.misc
References	<ttg9pl$301qu$1@dont-email.me> <DKqdnUe7v8BlT2b-nZ2dnZfqn_qdnZ2d@giganews.com> <ttgq6m$279gm$25@dont-email.me> <op.10zzw9sea3w0dxdave@hodgins.homeip.net> <t2aucjxrkf.ln2@Telcontar.valinor> <tthv4d$27bbi$22@dont-email.me> <vacucjxlnh.ln2@Telcontar.valinor> <tthvvq$27bbi$26@dont-email.me> <slrntvqvr2.dmi.spamtrap42@one.localnet> <du71djxs8i.ln2@Telcontar.valinor>
From	"28A.I873" <28A.I873@noabzba.net>
Organization	mitotic resell
Date	Wed, 1 Mar 2023 01:32:59 -0500
User-Agent	Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0
MIME-Version	1.0
In-Reply-To	<du71djxs8i.ln2@Telcontar.valinor>
Content-Type	text/plain; charset=utf-8; format=flowed
Content-Language	en-US
Content-Transfer-Encoding	8bit
Message-ID	<1JScnZYeWsEBbGP-nZ2dnZfqnPudnZ2d@earthlink.com> (permalink)
Lines	71
X-Usenet-Provider	http://www.giganews.com
NNTP-Posting-Host	68.222.41.46
X-Trace	sv3-LIn/t8Dj2B8SiPp/rQ/qiwDKF/wtHtVkOjwW6qyhEN0f0GZp9ZhnatDCoZACijeujCO72F3oYp8aK1X!gpbYIMjP6JEcwldB+J/TGvCecRkGhZtAJ/VPSJ6zloPrc5Asq39WDELwQC00BDd7g6q/xcN4C2QZ!iZBpbNEVdiBj3zh8vQw=
X-Abuse-and-DMCA-Info	Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info	Otherwise we will be unable to process your complaint properly
X-Postfilter	1.3.40
Xref	csiph.com comp.os.linux.misc:37338

Show key headers only | View raw

On 2/28/23 7:16 AM, Carlos E.R. wrote:
> On 2023-02-28 05:13, Robert Riches wrote:
>> On 2023-02-27, The Natural Philosopher <tnp@invalid.invalid> wrote:
>>> On 27/02/2023 10:13, Carlos E.R. wrote:
>>>> On 2023-02-27 11:02, The Natural Philosopher wrote:
>>>>> On 27/02/2023 09:34, Carlos E.R. wrote:
>>>>>> On 2023-02-27 01:06, David W. Hodgins wrote:
>>>>>>> On Sun, 26 Feb 2023 18:32:38 -0500, The Natural Philosopher
>>>>>>> <tnp@invalid.invalid> wrote:
>>>>>>>> I am pretty sure generally NO.
>>>>>>>> Otherwise databases would have a hard time working
>>>>>>>
>>>>>>> Data base applications work by having one thread that does the
>>>>>>> physical i/o for each file that contains the database. Multiple
>>>>>>> applications can use the database, but they don't do the i/o to the
>>>>>>> disk.
>>>>>>
>>>>>> Not all database applications work that way.
>>>>>>
>>>>>> For example, in MsDOS an application could lock for write a section
>>>>>> of a file, write that, then remove the lock. Another application
>>>>>> could be reading the same file, even writing in another section.
>>>>>>
>>>>>> This functionality was an add on: you needed to run the optional
>>>>>> share.exe. But Windows had it natively.
>>>>>>
>>>>>> I believe Microsoft Access works like that.
>>>>>>
>>>>>>
>>>>>> I am not sure this behaviour can be done in Linux. Long ago it could
>>>>>> not.
>>>>>>
>>>>> File lockining always existed at the level of IIRC whole files.
>>>>> But obliviously it is far far easier to have a databse engine
>>>>> accepting all requests and using (at least) just one process, if not
>>>>> one thread, to do all I/O
>>>>
>>>> Easier, depends. MS Access is trivially easy to use (for simple 
>>>> databases).
>>>>
>>> You call that a database? I dont. Any more than SqlLite is a
>>> database...both are single user/process  access only.
>>
>> Many of the hits from this web search disagree:
>>
>> https://duckduckgo.com/?q=sqlitemultiple+processes&hps=1&start=1&ia=web
>>
>> This FAQ answer appears fairly authoritative:
>>
>> https://www.sqlite.org/faq.html#q5
> 
> Interesting.


   "Concurrency" is a PAIN IN THE ASS at the programming
   level !

   The most common solution are uniquely-tagged files/processes
   and record-level locking. Alas record-locks DO tend to go
   wonky eventually because users find SOME unique way to
   screw up. "QuickBooks Multi-User", for example, will go
   insane every month or two and you have to reboot the server
   to restore multi-user access. Users tried to abort, or
   rebooted, in the middle of an update too often and ....

   There are also 'all-access' files/records/data-frames which
   are "live" ... ie you can be looking at it, able to edit it,
   but anything another user does immediately updates YOUR view.
   I think WikiPedia is sort-of that way - "dueling editors" is
   a thing that CAN happen. Some other "collaborative" documentation
   systems are like that too - everybody's live.

Back to comp.os.linux.misc | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

Contents of file changed while application is reading it Clark Smith <noaddress@nowhere.net> - 2023-02-26 18:52 +0000
  Re: Contents of file changed while application is reading it Rich <rich@example.invalid> - 2023-02-26 19:20 +0000
  Re: Contents of file changed while application is reading it Robert Heller <heller@deepsoft.com> - 2023-02-26 21:45 +0000
    Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-26 23:05 +0100
      Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-26 23:38 +0000
    Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-26 23:32 +0000
      Re: Contents of file changed while application is reading it "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2023-02-26 19:06 -0500
        Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-27 00:26 +0000
          Re: Contents of file changed while application is reading it "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2023-02-26 20:48 -0500
          Re: Contents of file changed while application is reading it Richard Kettlewell <invalid@invalid.invalid> - 2023-02-27 09:03 +0000
            Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-27 09:58 +0000
              Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-27 11:16 +0100
              Re: Contents of file changed while application is reading it Richard Kettlewell <invalid@invalid.invalid> - 2023-02-27 15:20 +0000
        Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-27 10:34 +0100
          Re: Contents of file changed while application is reading it Richard Kettlewell <invalid@invalid.invalid> - 2023-02-27 09:49 +0000
            Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-27 11:13 +0100
          Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-27 10:02 +0000
            Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-27 11:13 +0100
              Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-27 10:17 +0000
                Re: Contents of file changed while application is reading it "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2023-02-27 12:27 -0500
                Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-27 19:19 +0100
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-02-27 21:46 -0500
                Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-28 13:33 +0100
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-02-28 10:49 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-28 16:21 +0000
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-01 01:05 -0500
                Re: Contents of file changed while application is reading it Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2023-03-01 21:57 +0000
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-01 22:53 -0500
                Re: Contents of file changed while application is reading it Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2023-03-02 19:06 +0000
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-02 23:08 -0500
                Re: Contents of file changed while application is reading it Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2023-03-03 05:23 +0000
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-03 09:36 +0000
                Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-03-03 11:19 +0100
                Re: Contents of file changed while application is reading it Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2023-03-03 15:58 +0000
                Re: Contents of file changed while application is reading it "Carlos E. R." <robin_listas@es.invalid> - 2023-03-03 18:47 +0100
                Re: Contents of file changed while application is reading it Rich <rich@example.invalid> - 2023-03-04 16:24 +0000
                Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-03-04 18:40 +0100
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-03 18:44 +0000
                Re: Contents of file changed while application is reading it Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2023-03-04 01:25 +0000
                Re: Contents of file changed while application is reading it Rich <rich@example.invalid> - 2023-03-04 16:21 +0000
                Re: Contents of file changed while application is reading it "28B.I874" <28B.I874@noabzba.net> - 2023-03-04 23:55 -0500
                Re: Contents of file changed while application is reading it Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2023-03-05 05:35 +0000
                Re: Contents of file changed while application is reading it Allodoxaphobia <trepidation@example.net> - 2023-03-05 13:48 +0000
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-05 14:01 +0000
                Re: Contents of file changed while application is reading it Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2023-03-05 19:16 +0000
                Re: Contents of file changed while application is reading it "28B.I874" <28B.I874@noabzba.net> - 2023-03-06 00:43 -0500
                Re: Contents of file changed while application is reading it "28B.I874" <28B.I874@noabzba.net> - 2023-03-06 00:42 -0500
                Re: Contents of file changed while application is reading it "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2023-02-28 12:01 -0500
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-01 01:17 -0500
                Re: Contents of file changed while application is reading it Robert Riches <spamtrap42@jacob21819.net> - 2023-02-28 04:13 +0000
                Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-28 13:16 +0100
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-01 01:32 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-01 10:30 +0000
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-01 22:48 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-02 09:41 +0000
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-02 23:39 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-03 09:28 +0000
                Re: Contents of file changed while application is reading it "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2023-03-03 12:16 -0500
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-04 01:36 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-04 07:15 +0000
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-04 02:47 -0500
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-04 01:12 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-04 06:51 +0000
                Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-03-04 03:32 -0500
                Re: Contents of file changed while application is reading it Richard Kettlewell <invalid@invalid.invalid> - 2023-03-04 09:54 +0000
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-04 10:09 +0000
                Re: Contents of file changed while application is reading it Richard Kettlewell <invalid@invalid.invalid> - 2023-03-04 11:22 +0000
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-04 11:58 +0000
                Re: Contents of file changed while application is reading it Richard Kettlewell <invalid@invalid.invalid> - 2023-03-05 16:43 +0000
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-06 09:20 +0000
                Re: Contents of file changed while application is reading it "28B.I874" <28B.I874@noabzba.net> - 2023-03-04 20:24 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-05 13:40 +0000
                Re: Contents of file changed while application is reading it Dan Espen <dan1espen@gmail.com> - 2023-03-05 11:29 -0500
                Re: Contents of file changed while application is reading it "28B.I874" <28B.I874@noabzba.net> - 2023-03-06 01:21 -0500
                Re: Contents of file changed while application is reading it "28B.I874" <28B.I874@noabzba.net> - 2023-03-06 01:06 -0500
                Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-03-06 09:28 +0000
                Re: Contents of file changed while application is reading it "28B.I874" <28B.I874@noabzba.net> - 2023-03-06 08:54 -0500
  Re: Contents of file changed while application is reading it Dan Espen <dan1espen@gmail.com> - 2023-02-26 17:35 -0500
    Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-26 23:39 +0000
      Re: Contents of file changed while application is reading it "28A.I873" <28A.I873@noabzba.net> - 2023-02-26 22:42 -0500
    Re: Contents of file changed while application is reading it "Carlos E.R." <robin_listas@es.invalid> - 2023-02-27 10:45 +0100
  Re: Contents of file changed while application is reading it The Natural Philosopher <tnp@invalid.invalid> - 2023-02-26 23:31 +0000

csiph-web