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Groups > comp.os.linux.misc > #90165 > unrolled thread

/dev/tcp

Started byEli the Bearded <*@eli.users.panix.com>
First post2026-08-19 21:20 +0000
Last post2026-08-24 19:08 +0100
Articles 20 on this page of 137 — 18 participants

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Contents

  /dev/tcp Eli the Bearded <*@eli.users.panix.com> - 2026-08-19 21:20 +0000
    Re: /dev/tcp Richard Kettlewell <invalid@invalid.invalid> - 2026-08-19 23:53 +0100
    Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-19 23:42 +0000
      Re: /dev/tcp Eli the Bearded <*@eli.users.panix.com> - 2026-08-20 00:59 +0000
        Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-20 03:59 +0000
          Re: /dev/tcp Nuno Silva <nunojsilva@invalid.invalid> - 2026-08-20 10:10 +0100
          Re: /dev/tcp Eli the Bearded <*@eli.users.panix.com> - 2026-08-20 18:15 +0000
            Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-20 23:30 +0000
              Re: /dev/tcp Nuno Silva <nunojsilva@invalid.invalid> - 2026-08-21 01:18 +0100
              Re: /dev/tcp Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-08-21 09:52 +0200
                Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-21 08:12 +0000
                  Re: /dev/tcp Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-08-21 11:16 +0200
                    Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-21 22:57 +0000
                      Re: /dev/tcp Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-08-22 06:17 +0200
                Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-21 21:50 -0400
                Re: /dev/tcp Anssi Saari <anssi.saari@usenet.mail.kapsi.fi> - 2026-08-24 17:42 +0300
                  Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-24 23:53 +0000
                  Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-25 02:27 -0400
              Re: /dev/tcp vallor <vallor@vallor.earth> - 2026-08-23 00:56 +0000
                Re: /dev/tcp Rich <rich@example.invalid> - 2026-08-23 04:01 +0000
                  Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-23 03:37 -0400
                    Re: /dev/tcp "Carlos E.R." <robin_listas@es.invalid> - 2026-08-23 13:50 +0200
                      Re: /dev/tcp vallor <vallor@vallor.earth> - 2026-08-23 22:28 +0000
                        Re: /dev/tcp "Carlos E.R." <robin_listas@es.invalid> - 2026-08-24 09:35 +0200
                          Overwriting with random data (was: Re: /dev/tcp) Nuno Silva <nunojsilva@invalid.invalid> - 2026-08-24 11:10 +0100
                            Re: Overwriting with random data "Carlos E.R." <robin_listas@es.invalid> - 2026-08-24 20:34 +0200
                              Re: Overwriting with random data Richard Kettlewell <invalid@invalid.invalid> - 2026-08-24 20:57 +0100
                                Re: Overwriting with random data "Carlos E.R." <robin_listas@es.invalid> - 2026-08-24 22:26 +0200
                                  Re: Overwriting with random data c186282 <c186282@nnada.net> - 2026-08-25 02:39 -0400
                                    Re: Overwriting with random data Richard Kettlewell <invalid@invalid.invalid> - 2026-08-25 08:45 +0100
                                      Re: Overwriting with random data c186282 <c186282@nnada.net> - 2026-08-25 21:39 -0400
                                        Re: Overwriting with random data Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2026-08-26 18:08 +0000
                                    Re: Overwriting with random data "Carlos E.R." <robin_listas@es.invalid> - 2026-08-25 11:36 +0200
                                      Re: Overwriting with random data Richard Kettlewell <invalid@invalid.invalid> - 2026-08-25 15:19 +0100
                                        Re: Overwriting with random data c186282 <c186282@nnada.net> - 2026-08-26 03:33 -0400
                                          Re: Overwriting with random data The Natural Philosopher <tnp@invalid.invalid> - 2026-08-26 09:18 +0100
                                            Re: Overwriting with random data rbowman <bowman@montana.com> - 2026-08-26 17:34 +0000
                                    Re: Overwriting with random data The Natural Philosopher <tnp@invalid.invalid> - 2026-08-25 12:12 +0100
                                      Re: Overwriting with random data c186282 <c186282@nnada.net> - 2026-08-26 00:09 -0400
                                        Re: Overwriting with random data The Natural Philosopher <tnp@invalid.invalid> - 2026-08-26 08:52 +0100
                          Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-25 00:37 -0400
                      Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-24 00:31 -0400
                        Re: /dev/tcp "Carlos E.R." <robin_listas@es.invalid> - 2026-08-24 09:45 +0200
                    Re: /dev/tcp The Natural Philosopher <tnp@invalid.invalid> - 2026-08-23 12:52 +0100
                  Re: /dev/tcp The Natural Philosopher <tnp@invalid.invalid> - 2026-08-23 12:50 +0100
    Re: /dev/tcp Rich <rich@example.invalid> - 2026-08-20 13:50 +0000
      Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-20 13:02 -0400
        Re: /dev/tcp Rich <rich@example.invalid> - 2026-08-20 18:26 +0000
        Re: /dev/tcp The Natural Philosopher <tnp@invalid.invalid> - 2026-08-21 13:54 +0100
          Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-21 22:57 -0400
            Re: /dev/tcp "Carlos E.R." <robin_listas@es.invalid> - 2026-08-22 21:47 +0200
              The hammer is best (Was: /dev/tcp) gazelle@shell.xmission.com (Kenny McCormack) - 2026-08-22 23:50 +0000
                Re: The hammer is best (Was: /dev/tcp) c186282 <c186282@nnada.net> - 2026-08-23 04:28 -0400
                Re: The hammer is best Richard Kettlewell <invalid@invalid.invalid> - 2026-08-23 10:14 +0100
                  Re: The hammer is best "Carlos E.R." <robin_listas@es.invalid> - 2026-08-23 13:55 +0200
                    Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-23 13:16 +0100
                      Re: The hammer is best Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-08-23 21:20 +0200
                        Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-24 02:18 -0400
                        Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-24 11:26 +0100
                          Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-25 02:06 -0400
                            Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-25 12:18 +0100
                              Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-26 00:51 -0400
                      Re: The hammer is best Joed Oakes <lost@noway.home.invalid> - 2026-08-23 19:42 -0400
                        Re: The hammer is best Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-23 23:56 +0000
                          Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-24 02:25 -0400
                        Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-24 01:14 +0000
                        Re: The hammer is best "Carlos E.R." <robin_listas@es.invalid> - 2026-08-24 09:50 +0200
                          Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-25 00:56 -0400
                      Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-24 00:53 -0400
                        Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-24 06:42 +0000
                          Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-24 23:34 -0400
                            Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-25 04:08 +0000
                              Re: The hammer is best "Carlos E.R." <robin_listas@es.invalid> - 2026-08-25 11:29 +0200
                                Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-25 18:52 +0000
                                  Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-26 04:19 -0400
                                    Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-26 09:29 +0100
                                      Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-26 17:03 +0000
                                        Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-26 21:31 +0100
                                Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-25 22:18 -0400
                        Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-24 11:28 +0100
                          Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-25 02:07 -0400
                            Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-25 06:39 +0000
                              Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-25 12:23 +0100
                                Re: The hammer is best Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2026-08-25 18:26 +0000
                                  Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-25 20:05 +0100
                                    Re: The hammer is best "Carlos E.R." <robin_listas@es.invalid> - 2026-08-25 21:43 +0200
                                      Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-26 08:35 +0100
                                    Re: The hammer is best Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2026-08-25 20:21 +0000
                                      Re: The hammer is best "Carlos E.R." <robin_listas@es.invalid> - 2026-08-25 23:14 +0200
                                Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-25 19:08 +0000
                                  Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-26 04:38 -0400
                                    Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-26 10:22 +0100
                                      Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-26 17:26 +0000
                                Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-26 01:49 -0400
                            Re: The hammer is best The Natural Philosopher <tnp@invalid.invalid> - 2026-08-25 12:20 +0100
                              Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-26 01:23 -0400
                  Re: The hammer is best c186282 <c186282@nnada.net> - 2026-08-23 22:16 -0400
        Re: /dev/tcp Geoff Clare <geoff@clare.See-My-Signature.invalid> - 2026-08-21 13:41 +0100
          Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-21 22:58 +0000
          Re: /dev/tcp c186282 <c186282@nnada.net> - 2026-08-21 22:28 -0400
            ksh (was: /dev/tcp) Geoff Clare <geoff@clare.See-My-Signature.invalid> - 2026-08-24 13:56 +0100
              Bash vs. ksh - Does it matter? And the 'vi' mode thing... (Was: ksh (was: /dev/tcp)) gazelle@shell.xmission.com (Kenny McCormack) - 2026-08-24 14:57 +0000
              Re: ksh (was: /dev/tcp) Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-24 21:08 +0000
                Re: ksh (was: /dev/tcp) gazelle@shell.xmission.com (Kenny McCormack) - 2026-08-24 21:28 +0000
                Re: ksh (was: /dev/tcp) rbowman <bowman@montana.com> - 2026-08-25 01:11 +0000
                Re: ksh (was: /dev/tcp) Geoff Clare <geoff@clare.See-My-Signature.invalid> - 2026-08-25 13:25 +0100
                  Re: ksh (was: /dev/tcp) Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-25 21:58 +0000
                    Re: ksh (was: /dev/tcp) Geoff Clare <geoff@clare.See-My-Signature.invalid> - 2026-08-26 13:34 +0100
              Re: ksh c186282 <c186282@nnada.net> - 2026-08-25 02:25 -0400
                Re: ksh rbowman <bowman@montana.com> - 2026-08-25 06:52 +0000
                  Re: ksh The Natural Philosopher <tnp@invalid.invalid> - 2026-08-25 12:27 +0100
                    Re: ksh Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2026-08-25 18:26 +0000
                      Re: ksh Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-25 22:03 +0000
                      Re: ksh c186282 <c186282@nnada.net> - 2026-08-26 04:04 -0400
                        Re: ksh rbowman <bowman@montana.com> - 2026-08-26 18:00 +0000
                    Re: ksh c186282 <c186282@nnada.net> - 2026-08-26 02:35 -0400
                      Re: ksh rbowman <bowman@montana.com> - 2026-08-26 18:17 +0000
                Re: ksh Marco Moock <mm@dorfdsl.de> - 2026-08-25 09:56 +0200
                  Re: ksh "Carlos E.R." <robin_listas@es.invalid> - 2026-08-25 11:24 +0200
                    Re: ksh Marc Haber <mh+usenetspam2616@zugschl.us> - 2026-08-25 20:36 +0200
                      Re: ksh rbowman <bowman@montana.com> - 2026-08-26 04:23 +0000
                        Re: ksh "Carlos E.R." <robin_listas@es.invalid> - 2026-08-26 10:04 +0200
                          Re: ksh Nuno Silva <nunojsilva@invalid.invalid> - 2026-08-26 10:03 +0100
                    Re: ksh c186282 <c186282@nnada.net> - 2026-08-25 21:50 -0400
                  Re: ksh The Natural Philosopher <tnp@invalid.invalid> - 2026-08-25 12:27 +0100
                    Re: ksh c186282 <c186282@nnada.net> - 2026-08-26 02:43 -0400
                  Re: ksh Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-25 22:01 +0000
                    Re: ksh "Carlos E.R." <robin_listas@es.invalid> - 2026-08-26 01:32 +0200
                  Re: ksh c186282 <c186282@nnada.net> - 2026-08-25 21:46 -0400
                    Re: ksh rbowman <bowman@montana.com> - 2026-08-26 04:25 +0000
      Re: /dev/tcp Eli the Bearded <*@eli.users.panix.com> - 2026-08-20 18:22 +0000
        Re: /dev/tcp The Natural Philosopher <tnp@invalid.invalid> - 2026-08-21 13:57 +0100
    Re: /dev/tcp Lars Poulsen <lars@beagle-ears.com> - 2026-08-23 06:37 -0700
      Re: /dev/tcp Richard Kettlewell <invalid@invalid.invalid> - 2026-08-23 14:49 +0100
      Re: /dev/tcp The Natural Philosopher <tnp@invalid.invalid> - 2026-08-23 16:13 +0100
      Re: /dev/tcp Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-23 22:31 +0000
        Re: /dev/tcp Richard Kettlewell <invalid@invalid.invalid> - 2026-08-24 19:08 +0100

Page 2 of 7 — ← Prev page 1 [2] 3 4 5 6 7  Next page →


#90376

Fromc186282 <c186282@nnada.net>
Date2026-08-23 03:37 -0400
Message-ID<5b2dnb6l8sPvPhf3nZ2dnZfqnPGdnZ2d@giganews.com>
In reply to#90370
On 8/23/26 00:01, Rich wrote:
> vallor <vallor@vallor.earth> wrote:
>> At Thu, 20 Aug 2026 23:30:40 -0000 (UTC), Lawrence D’Oliveiro <ldo@nz.invalid> wrote:
>>
>>> On Thu, 20 Aug 2026 18:15:27 -0000 (UTC), Eli the Bearded wrote:
>>>
>>>> In comp.os.linux.misc, Lawrence DOliveiro <ldo@nz.invalid> wrote:
>>>>>
>>>>> On Thu, 20 Aug 2026 00:59:41 -0000 (UTC), Eli the Bearded wrote:
>>>>>>
>>>>>> This came up in the context of "how to test network on a system
>>>>>> with no root and no helpful utilities installed."
>>>>>
>>>>> So a version of bash that supports /dev/tcp is somehow excluded
>>>>> from that “no helpful utilities installed” assumption?
>>>>
>>>> The system being tested did not have bash installed. Busybox
>>>> provided /bin/sh there.
>>>
>>> I thought you said you were testing the *network*, not the *system*.
>>>
>>> You can’t really do that (in general) without access to a proper
>>> suite of diagnostic tools.
>>>
>>> In such a situation, I would try one (or both) of two things:
>>>
>>> * Reboot the machine with a SystemRescue USB stick
>>>    <https://www.system-rescue.org/>. That way, I get unconstrained
>>>    access to an entire system custom-designed precisely for running
>>>    diagnostics.
>>> * Bring in my own machine, which already has my own custom setup on
>>>    it, and connect it to the network.
>>>
>>> Both of these also have the advantage of ruling out screwups in the
>>> existing OS installation.
>>>
>>> And if you’re saying the situation would not allow me to do either of
>>> these things, then I would not have accepted the job in the first
>>> place.
>>
>> Have you ever agreed with someone?
> 
> It's kind of the troll ethos, disagreeing brings on more chaos.


   There are always a few ... being negative/disagreeable
   or, worse, All-Superior is Their Main Thing. They feel
   they "Gain Power" that way.

   No, I'm not basing that on Freud or Jung - just long
   experience.

   I pref the "Let's All Get Along" approach. Everything
   goes MUCH smoother and solutions, rather than conflict,
   is the usual result.

   ANYway, /dev/tcp does have uses. It's worth exploring.
   Maybe YOU can find a use to suit YOUR needs/desires.
   I used it for a custom disk-scan/wipe app (had to
   use a 'C' module because huge track/cluster/byte numbers
   were needed for modern mag drives - the main app was
   in Lazarus for the pretty display and buttons).

   Note Lazarus/FPC *says* it supports huge seek numbers
   but DOESN'T ... limited to maybe 4gb.

[toc] | [prev] | [next] | [standalone]


#90387

From"Carlos E.R." <robin_listas@es.invalid>
Date2026-08-23 13:50 +0200
Message-ID<6d3rlmxqg4.ln2@Telcontar.valinor>
In reply to#90376
On 2026-08-23 09:37, c186282 wrote:
> On 8/23/26 00:01, Rich wrote:
>> vallor <vallor@vallor.earth> wrote:
>>> At Thu, 20 Aug 2026 23:30:40 -0000 (UTC), Lawrence D’Oliveiro 
>>> <ldo@nz.invalid> wrote:
>>>
>>>> On Thu, 20 Aug 2026 18:15:27 -0000 (UTC), Eli the Bearded wrote:
>>>>
>>>>> In comp.os.linux.misc, Lawrence DOliveiro <ldo@nz.invalid> wrote:
>>>>>>
>>>>>> On Thu, 20 Aug 2026 00:59:41 -0000 (UTC), Eli the Bearded wrote:
>>>>>>>
>>>>>>> This came up in the context of "how to test network on a system
>>>>>>> with no root and no helpful utilities installed."
>>>>>>
>>>>>> So a version of bash that supports /dev/tcp is somehow excluded
>>>>>> from that “no helpful utilities installed” assumption?
>>>>>
>>>>> The system being tested did not have bash installed. Busybox
>>>>> provided /bin/sh there.
>>>>
>>>> I thought you said you were testing the *network*, not the *system*.
>>>>
>>>> You can’t really do that (in general) without access to a proper
>>>> suite of diagnostic tools.
>>>>
>>>> In such a situation, I would try one (or both) of two things:
>>>>
>>>> * Reboot the machine with a SystemRescue USB stick
>>>>    <https://www.system-rescue.org/>. That way, I get unconstrained
>>>>    access to an entire system custom-designed precisely for running
>>>>    diagnostics.
>>>> * Bring in my own machine, which already has my own custom setup on
>>>>    it, and connect it to the network.
>>>>
>>>> Both of these also have the advantage of ruling out screwups in the
>>>> existing OS installation.
>>>>
>>>> And if you’re saying the situation would not allow me to do either of
>>>> these things, then I would not have accepted the job in the first
>>>> place.
>>>
>>> Have you ever agreed with someone?
>>
>> It's kind of the troll ethos, disagreeing brings on more chaos.
> 
> 
>    There are always a few ... being negative/disagreeable
>    or, worse, All-Superior is Their Main Thing. They feel
>    they "Gain Power" that way.
> 
>    No, I'm not basing that on Freud or Jung - just long
>    experience.
> 
>    I pref the "Let's All Get Along" approach. Everything
>    goes MUCH smoother and solutions, rather than conflict,
>    is the usual result.
> 
>    ANYway, /dev/tcp does have uses. It's worth exploring.
>    Maybe YOU can find a use to suit YOUR needs/desires.
>    I used it for a custom disk-scan/wipe app (had to
>    use a 'C' module because huge track/cluster/byte numbers
>    were needed for modern mag drives - the main app was
>    in Lazarus for the pretty display and buttons).
> 
>    Note Lazarus/FPC *says* it supports huge seek numbers
>    but DOESN'T ... limited to maybe 4gb.

I wrote a program that writes bytes on big partitions.


excerpted:

const
      sourcefilename = './BigRandom';
      rawdest: string = '';     // example: '/dev/sda11'

      shuflecount = 1024;
      arraysize = 1023;
      ChunkSz=1048576;
type
      tCacho= array [1..ChunkSz] of byte;

var
    Fin, Fout: file of tCacho;
    gotresult: Word;

    BigData : array [1..shuflecount] of tCacho;
    OutputIndex : Int64;	// counts MiB written.


begin

// writes one MiB
       {$I-}write(Fout,BigData[RandomIndex]);{$I+}
       gotresult:= ioresult;



The purpose of the program is to fast fill a partition or disk with 
nearly true random data. It is as fast as dd could be.



-- 
Cheers, Carlos.
ES🇪🇸, EU🇪🇺;

[toc] | [prev] | [next] | [standalone]


#90414

Fromvallor <vallor@vallor.earth>
Date2026-08-23 22:28 +0000
Message-ID<116fs5p$28rhg$2@dont-email.me>
In reply to#90387
At Sun, 23 Aug 2026 13:50:30 +0200, "Carlos E.R." <robin_listas@es.invalid> wrote:

> On 2026-08-23 09:37, c186282 wrote:
> > On 8/23/26 00:01, Rich wrote:
> >> vallor <vallor@vallor.earth> wrote:
> >>> At Thu, 20 Aug 2026 23:30:40 -0000 (UTC), Lawrence D’Oliveiro 
> >>> <ldo@nz.invalid> wrote:
> >>>
> >>>> On Thu, 20 Aug 2026 18:15:27 -0000 (UTC), Eli the Bearded wrote:
> >>>>
> >>>>> In comp.os.linux.misc, Lawrence DOliveiro <ldo@nz.invalid> wrote:
> >>>>>>
> >>>>>> On Thu, 20 Aug 2026 00:59:41 -0000 (UTC), Eli the Bearded wrote:
> >>>>>>>
> >>>>>>> This came up in the context of "how to test network on a system
> >>>>>>> with no root and no helpful utilities installed."
> >>>>>>
> >>>>>> So a version of bash that supports /dev/tcp is somehow excluded
> >>>>>> from that “no helpful utilities installed” assumption?
> >>>>>
> >>>>> The system being tested did not have bash installed. Busybox
> >>>>> provided /bin/sh there.
> >>>>
> >>>> I thought you said you were testing the *network*, not the *system*.
> >>>>
> >>>> You can’t really do that (in general) without access to a proper
> >>>> suite of diagnostic tools.
> >>>>
> >>>> In such a situation, I would try one (or both) of two things:
> >>>>
> >>>> * Reboot the machine with a SystemRescue USB stick
> >>>>    <https://www.system-rescue.org/>. That way, I get unconstrained
> >>>>    access to an entire system custom-designed precisely for running
> >>>>    diagnostics.
> >>>> * Bring in my own machine, which already has my own custom setup on
> >>>>    it, and connect it to the network.
> >>>>
> >>>> Both of these also have the advantage of ruling out screwups in the
> >>>> existing OS installation.
> >>>>
> >>>> And if you’re saying the situation would not allow me to do either of
> >>>> these things, then I would not have accepted the job in the first
> >>>> place.
> >>>
> >>> Have you ever agreed with someone?
> >>
> >> It's kind of the troll ethos, disagreeing brings on more chaos.
> > 
> > 
> >    There are always a few ... being negative/disagreeable
> >    or, worse, All-Superior is Their Main Thing. They feel
> >    they "Gain Power" that way.
> > 
> >    No, I'm not basing that on Freud or Jung - just long
> >    experience.
> > 
> >    I pref the "Let's All Get Along" approach. Everything
> >    goes MUCH smoother and solutions, rather than conflict,
> >    is the usual result.
> > 
> >    ANYway, /dev/tcp does have uses. It's worth exploring.
> >    Maybe YOU can find a use to suit YOUR needs/desires.
> >    I used it for a custom disk-scan/wipe app (had to
> >    use a 'C' module because huge track/cluster/byte numbers
> >    were needed for modern mag drives - the main app was
> >    in Lazarus for the pretty display and buttons).
> > 
> >    Note Lazarus/FPC *says* it supports huge seek numbers
> >    but DOESN'T ... limited to maybe 4gb.
> 
> I wrote a program that writes bytes on big partitions.
> 
> 
> excerpted:
> 
> const
>       sourcefilename = './BigRandom';
>       rawdest: string = '';     // example: '/dev/sda11'
> 
>       shuflecount = 1024;
>       arraysize = 1023;
>       ChunkSz=1048576;
> type
>       tCacho= array [1..ChunkSz] of byte;
> 
> var
>     Fin, Fout: file of tCacho;
>     gotresult: Word;
> 
>     BigData : array [1..shuflecount] of tCacho;
>     OutputIndex : Int64;	// counts MiB written.
> 
> 
> begin
> 
> // writes one MiB
>        {$I-}write(Fout,BigData[RandomIndex]);{$I+}
>        gotresult:= ioresult;
> 
> 
> 
> The purpose of the program is to fast fill a partition or disk with 
> nearly true random data. It is as fast as dd could be.

SHRED(1)                 User Commands                 SHRED(1)

NAME
       shred  -  overwrite  a  file  to  hide its contents, and
       optionally delete it

SYNOPSIS
       shred [OPTION]... FILE...

DESCRIPTION
       Overwrite the specified FILE(s) repeatedly, in order  to
       make  it harder for even very expensive hardware probing
       to recover the data.


-- 
-v System76 Thelio Mega v1.1 x86_64 Mem: 258G
   OS: Linux 7.2.0 D: Mint 22.3 DE: Xfce 4.18 (X11)
   NVIDIA GeForce RTX 3090Ti (24G) (610.57.04)
   "Diplomacy is saying "nice doggy" until you find a rock."

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#90443

From"Carlos E.R." <robin_listas@es.invalid>
Date2026-08-24 09:35 +0200
Message-ID<6r8tlmxeb9.ln2@Telcontar.valinor>
In reply to#90414
On 2026-08-24 00:28, vallor wrote:
> At Sun, 23 Aug 2026 13:50:30 +0200, "Carlos E.R." <robin_listas@es.invalid> wrote:
> 
>> On 2026-08-23 09:37, c186282 wrote:
>>> On 8/23/26 00:01, Rich wrote:
>>>> vallor <vallor@vallor.earth> wrote:
>>>>> At Thu, 20 Aug 2026 23:30:40 -0000 (UTC), Lawrence D’Oliveiro
>>>>> <ldo@nz.invalid> wrote:
>>>>>
>>>>>> On Thu, 20 Aug 2026 18:15:27 -0000 (UTC), Eli the Bearded wrote:
>>>>>>
>>>>>>> In comp.os.linux.misc, Lawrence DOliveiro <ldo@nz.invalid> wrote:
>>>>>>>>
>>>>>>>> On Thu, 20 Aug 2026 00:59:41 -0000 (UTC), Eli the Bearded wrote:
>>>>>>>>>
>>>>>>>>> This came up in the context of "how to test network on a system
>>>>>>>>> with no root and no helpful utilities installed."
>>>>>>>>
>>>>>>>> So a version of bash that supports /dev/tcp is somehow excluded
>>>>>>>> from that “no helpful utilities installed” assumption?
>>>>>>>
>>>>>>> The system being tested did not have bash installed. Busybox
>>>>>>> provided /bin/sh there.
>>>>>>
>>>>>> I thought you said you were testing the *network*, not the *system*.
>>>>>>
>>>>>> You can’t really do that (in general) without access to a proper
>>>>>> suite of diagnostic tools.
>>>>>>
>>>>>> In such a situation, I would try one (or both) of two things:
>>>>>>
>>>>>> * Reboot the machine with a SystemRescue USB stick
>>>>>>     <https://www.system-rescue.org/>. That way, I get unconstrained
>>>>>>     access to an entire system custom-designed precisely for running
>>>>>>     diagnostics.
>>>>>> * Bring in my own machine, which already has my own custom setup on
>>>>>>     it, and connect it to the network.
>>>>>>
>>>>>> Both of these also have the advantage of ruling out screwups in the
>>>>>> existing OS installation.
>>>>>>
>>>>>> And if you’re saying the situation would not allow me to do either of
>>>>>> these things, then I would not have accepted the job in the first
>>>>>> place.
>>>>>
>>>>> Have you ever agreed with someone?
>>>>
>>>> It's kind of the troll ethos, disagreeing brings on more chaos.
>>>
>>>
>>>     There are always a few ... being negative/disagreeable
>>>     or, worse, All-Superior is Their Main Thing. They feel
>>>     they "Gain Power" that way.
>>>
>>>     No, I'm not basing that on Freud or Jung - just long
>>>     experience.
>>>
>>>     I pref the "Let's All Get Along" approach. Everything
>>>     goes MUCH smoother and solutions, rather than conflict,
>>>     is the usual result.
>>>
>>>     ANYway, /dev/tcp does have uses. It's worth exploring.
>>>     Maybe YOU can find a use to suit YOUR needs/desires.
>>>     I used it for a custom disk-scan/wipe app (had to
>>>     use a 'C' module because huge track/cluster/byte numbers
>>>     were needed for modern mag drives - the main app was
>>>     in Lazarus for the pretty display and buttons).
>>>
>>>     Note Lazarus/FPC *says* it supports huge seek numbers
>>>     but DOESN'T ... limited to maybe 4gb.
>>
>> I wrote a program that writes bytes on big partitions.
>>
>>
>> excerpted:
>>
>> const
>>        sourcefilename = './BigRandom';
>>        rawdest: string = '';     // example: '/dev/sda11'
>>
>>        shuflecount = 1024;
>>        arraysize = 1023;
>>        ChunkSz=1048576;
>> type
>>        tCacho= array [1..ChunkSz] of byte;
>>
>> var
>>      Fin, Fout: file of tCacho;
>>      gotresult: Word;
>>
>>      BigData : array [1..shuflecount] of tCacho;
>>      OutputIndex : Int64;	// counts MiB written.
>>
>>
>> begin
>>
>> // writes one MiB
>>         {$I-}write(Fout,BigData[RandomIndex]);{$I+}
>>         gotresult:= ioresult;
>>
>>
>>
>> The purpose of the program is to fast fill a partition or disk with
>> nearly true random data. It is as fast as dd could be.
> 
> SHRED(1)                 User Commands                 SHRED(1)
> 
> NAME
>         shred  -  overwrite  a  file  to  hide its contents, and
>         optionally delete it
> 
> SYNOPSIS
>         shred [OPTION]... FILE...
> 
> DESCRIPTION
>         Overwrite the specified FILE(s) repeatedly, in order  to
>         make  it harder for even very expensive hardware probing
>         to recover the data.

Not the same thing.


-- 
Cheers, Carlos.
ES🇪🇸, EU🇪🇺;

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#90446 — Overwriting with random data (was: Re: /dev/tcp)

FromNuno Silva <nunojsilva@invalid.invalid>
Date2026-08-24 11:10 +0100
SubjectOverwriting with random data (was: Re: /dev/tcp)
Message-ID<116h5be$2nco1$1@dont-email.me>
In reply to#90443
On 2026-08-24, Carlos E.R. wrote:

> On 2026-08-24 00:28, vallor wrote:
>> At Sun, 23 Aug 2026 13:50:30 +0200, "Carlos E.R." <robin_listas@es.invalid> wrote:
>
[snipping a lot to keep this shorter, apologies if I ended up snipping
too much]
>
>>> I wrote a program that writes bytes on big partitions.
>>>
>>>
>>> excerpted:
>>>
>>> const
>>>        sourcefilename = './BigRandom';
>>>        rawdest: string = '';     // example: '/dev/sda11'
>>>
>>>        shuflecount = 1024;
>>>        arraysize = 1023;
>>>        ChunkSz=1048576;
>>> type
>>>        tCacho= array [1..ChunkSz] of byte;
>>>
>>> var
>>>      Fin, Fout: file of tCacho;
>>>      gotresult: Word;
>>>
>>>      BigData : array [1..shuflecount] of tCacho;
>>>      OutputIndex : Int64;	// counts MiB written.
>>>
>>>
>>> begin
>>>
>>> // writes one MiB
>>>         {$I-}write(Fout,BigData[RandomIndex]);{$I+}
>>>         gotresult:= ioresult;
>>>
>>>
>>>
>>> The purpose of the program is to fast fill a partition or disk with
>>> nearly true random data. It is as fast as dd could be.
>>
>> SHRED(1)                 User Commands                 SHRED(1)
>>
>> NAME
>>         shred  -  overwrite  a  file  to  hide its contents, and
>>         optionally delete it
>>
>> SYNOPSIS
>>         shred [OPTION]... FILE...
>>
>> DESCRIPTION
>>         Overwrite the specified FILE(s) repeatedly, in order  to
>>         make  it harder for even very expensive hardware probing
>>         to recover the data.
>
> Not the same thing.

IIRC shred can do the same, and on block devices too, what's the
difference here? block sizes?

-- 
Nuno Silva

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#90457 — Re: Overwriting with random data

From"Carlos E.R." <robin_listas@es.invalid>
Date2026-08-24 20:34 +0200
SubjectRe: Overwriting with random data
Message-ID<vefulmxca.ln2@Telcontar.valinor>
In reply to#90446
On 2026-08-24 12:10, Nuno Silva wrote:
> On 2026-08-24, Carlos E.R. wrote:
> 
>> On 2026-08-24 00:28, vallor wrote:
>>> At Sun, 23 Aug 2026 13:50:30 +0200, "Carlos E.R." <robin_listas@es.invalid> wrote:
>>
> [snipping a lot to keep this shorter, apologies if I ended up snipping
> too much]
>>
>>>> I wrote a program that writes bytes on big partitions.
>>>>
>>>>
>>>> excerpted:
>>>>
>>>> const
>>>>         sourcefilename = './BigRandom';
>>>>         rawdest: string = '';     // example: '/dev/sda11'
>>>>
>>>>         shuflecount = 1024;
>>>>         arraysize = 1023;
>>>>         ChunkSz=1048576;
>>>> type
>>>>         tCacho= array [1..ChunkSz] of byte;
>>>>
>>>> var
>>>>       Fin, Fout: file of tCacho;
>>>>       gotresult: Word;
>>>>
>>>>       BigData : array [1..shuflecount] of tCacho;
>>>>       OutputIndex : Int64;	// counts MiB written.
>>>>
>>>>
>>>> begin
>>>>
>>>> // writes one MiB
>>>>          {$I-}write(Fout,BigData[RandomIndex]);{$I+}
>>>>          gotresult:= ioresult;
>>>>
>>>>
>>>>
>>>> The purpose of the program is to fast fill a partition or disk with
>>>> nearly true random data. It is as fast as dd could be.
>>>
>>> SHRED(1)                 User Commands                 SHRED(1)
>>>
>>> NAME
>>>          shred  -  overwrite  a  file  to  hide its contents, and
>>>          optionally delete it
>>>
>>> SYNOPSIS
>>>          shred [OPTION]... FILE...
>>>
>>> DESCRIPTION
>>>          Overwrite the specified FILE(s) repeatedly, in order  to
>>>          make  it harder for even very expensive hardware probing
>>>          to recover the data.
>>
>> Not the same thing.
> 
> IIRC shred can do the same, and on block devices too, what's the
> difference here? block sizes?


I mentioned my code because it accesses huge devices in pascal, way 
beyond 4G.

c186282 said:
   Note Lazarus/FPC *says* it supports huge seek numbers
   but DOESN'T ... limited to maybe 4gb.


Some functions work, others don't. This does not work:

const
      rawdest: string = '';     // example: '/dev/sda11'
      ChunkSz=1048576;

type
      tCacho= array [1..ChunkSz] of byte;

var
    Fin, Fout: file of tCacho;


begin

    rawdest:= ParamStr(1);
    writeln('Apparent size of ', rawdest, ' is ', filesize(Fout));


It writes '0' (I am currently erasing an 8TB disk)


Notice that I am not using a file of bytes, but a file of 1 MiB arrays. 
And I am not using seek, but writing contiguously.


Now the shred part.


Using true random data is slow, specially if the disk or partition is 
very big. Depends on how fast can the machine create new random data 
(see man random and urandom). So I do tricks to do it faster. And shred 
does it several times.

The algorithm I use is:

   Fill a 1 GiB file with true random data.
   Read that file into ram.
   repeat
      take 1 MiB of that and write it into the destination device
      advance
      Every 100 advances, replace 1 MiB of the array of random bytes
         with new random data
   until end of device


So, the data is truly random, but used repeatedly (and slowly renovated).

-- 
Cheers, Carlos.
ES🇪🇸, EU🇪🇺;

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#90463 — Re: Overwriting with random data

FromRichard Kettlewell <invalid@invalid.invalid>
Date2026-08-24 20:57 +0100
SubjectRe: Overwriting with random data
Message-ID<wwvfr03z3ye.fsf@LkoBDZeT.terraraq.uk>
In reply to#90457
"Carlos E.R." <robin_listas@es.invalid> writes:
> Using true random data is slow, specially if the disk or partition is
> very big. Depends on how fast can the machine create new random data
> (see man random and urandom). So I do tricks to do it faster.

With very few exceptions nobody uses true random[1] data directly.
/dev/random is a DRBG seeded from the random sources the kernel finds;
shred sees its internal RNG with 32 bytes from the kernel (strace
it...); I don’t know where you’re getting random data from but the
chances that it’s direct from a TRNG are negligible.

[1] in the sense described by
    e.g. https://link.springer.com/content/pdf/10.1007/978-3-540-85053-3_10.pdf

-- 
https://www.greenend.org.uk/rjk/

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#90465 — Re: Overwriting with random data

From"Carlos E.R." <robin_listas@es.invalid>
Date2026-08-24 22:26 +0200
SubjectRe: Overwriting with random data
Message-ID<71mulmxumi.ln2@Telcontar.valinor>
In reply to#90463
On 2026-08-24 21:57, Richard Kettlewell wrote:
> "Carlos E.R." <robin_listas@es.invalid> writes:
>> Using true random data is slow, specially if the disk or partition is
>> very big. Depends on how fast can the machine create new random data
>> (see man random and urandom). So I do tricks to do it faster.
> 
> With very few exceptions nobody uses true random[1] data directly.
> /dev/random is a DRBG seeded from the random sources the kernel finds;
> shred sees its internal RNG with 32 bytes from the kernel (strace
> it...); I don’t know where you’re getting random data from but the
> chances that it’s direct from a TRNG are negligible.

Normally

   dd if=/dev/urandom of=$BIGRANDOM count=1024 bs=1M

or in pascal

var
    randomsource : file of byte;
    x: Integer;
begin
    try
       assign(randomsource, '/dev/urandom');
       reset(randomsource);
       for x:= 1 to shuflecount do
          read(randomsource, BigData[Index, x]);
    finally
       close(randomsource);
    end;
end;


> 
> [1] in the sense described by
>      e.g. https://link.springer.com/content/pdf/10.1007/978-3-540-85053-3_10.pdf
> 


-- 
Cheers, Carlos.
ES🇪🇸, EU🇪🇺;

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#90495 — Re: Overwriting with random data

Fromc186282 <c186282@nnada.net>
Date2026-08-25 02:39 -0400
SubjectRe: Overwriting with random data
Message-ID<4R-dndpP7cWGpBD3nZ2dnZfqn_adnZ2d@giganews.com>
In reply to#90465
On 8/24/26 16:26, Carlos E.R. wrote:
> On 2026-08-24 21:57, Richard Kettlewell wrote:
>> "Carlos E.R." <robin_listas@es.invalid> writes:
>>> Using true random data is slow, specially if the disk or partition is
>>> very big. Depends on how fast can the machine create new random data
>>> (see man random and urandom). So I do tricks to do it faster.
>>
>> With very few exceptions nobody uses true random[1] data directly.
>> /dev/random is a DRBG seeded from the random sources the kernel finds;
>> shred sees its internal RNG with 32 bytes from the kernel (strace
>> it...); I don’t know where you’re getting random data from but the
>> chances that it’s direct from a TRNG are negligible.
> 
> Normally
> 
>    dd if=/dev/urandom of=$BIGRANDOM count=1024 bs=1M
> 
> or in pascal
> 
> var
>     randomsource : file of byte;
>     x: Integer;
> begin
>     try
>        assign(randomsource, '/dev/urandom');
>        reset(randomsource);
>        for x:= 1 to shuflecount do
>           read(randomsource, BigData[Index, x]);
>     finally
>        close(randomsource);
>     end;
> end;

   MIGHT not be as "random" as you hope. This has
   LONG been a problem.

   Rather than rely on some canned function, DO add
   some shit from very transient machine-related vars
   as well. Video vars, CPU temps, that kind of shit.
   STILL not really truly "random" - but a lot closer.

   If you want TRUE "random", I suspect some kind of
   little quantum device will be needed.

>>
>> [1] in the sense described by
>>      e.g. https://link.springer.com/content/ 
>> pdf/10.1007/978-3-540-85053-3_10.pdf
>>

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#90500 — Re: Overwriting with random data

FromRichard Kettlewell <invalid@invalid.invalid>
Date2026-08-25 08:45 +0100
SubjectRe: Overwriting with random data
Message-ID<wwvqzjmk5j7.fsf@LkoBDZeT.terraraq.uk>
In reply to#90495
c186282 <c186282@nnada.net> writes:
> On 8/24/26 16:26, Carlos E.R. wrote:
>> On 2026-08-24 21:57, Richard Kettlewell wrote:
>>> "Carlos E.R." <robin_listas@es.invalid> writes:
>>>> Using true random data is slow, specially if the disk or partition is
>>>> very big. Depends on how fast can the machine create new random data
>>>> (see man random and urandom). So I do tricks to do it faster.
>>>
>>> With very few exceptions nobody uses true random[1] data directly.
>>> /dev/random is a DRBG seeded from the random sources the kernel finds;
>>> shred sees its internal RNG with 32 bytes from the kernel (strace
>>> it...); I don’t know where you’re getting random data from but the
>>> chances that it’s direct from a TRNG are negligible.
>> Normally
>>    dd if=/dev/urandom of=$BIGRANDOM count=1024 bs=1M
>> or in pascal
>> var
>>     randomsource : file of byte;
>>     x: Integer;
>> begin
>>     try
>>        assign(randomsource, '/dev/urandom');
>>        reset(randomsource);
>>        for x:= 1 to shuflecount do
>>           read(randomsource, BigData[Index, x]);
>>     finally
>>        close(randomsource);
>>     end;
>> end;
>
>   MIGHT not be as "random" as you hope. This has LONG been a problem.

Nonsense. It’s at least as random as Carlos or I hope. Read some
documentation for once.

-- 
https://www.greenend.org.uk/rjk/

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#90577 — Re: Overwriting with random data

Fromc186282 <c186282@nnada.net>
Date2026-08-25 21:39 -0400
SubjectRe: Overwriting with random data
Message-ID<ZfqcnXlt_dS92RP3nZ2dnZfqnPWdnZ2d@giganews.com>
In reply to#90500
On 8/25/26 03:45, Richard Kettlewell wrote:
> c186282 <c186282@nnada.net> writes:
>> On 8/24/26 16:26, Carlos E.R. wrote:
>>> On 2026-08-24 21:57, Richard Kettlewell wrote:
>>>> "Carlos E.R." <robin_listas@es.invalid> writes:
>>>>> Using true random data is slow, specially if the disk or partition is
>>>>> very big. Depends on how fast can the machine create new random data
>>>>> (see man random and urandom). So I do tricks to do it faster.
>>>>
>>>> With very few exceptions nobody uses true random[1] data directly.
>>>> /dev/random is a DRBG seeded from the random sources the kernel finds;
>>>> shred sees its internal RNG with 32 bytes from the kernel (strace
>>>> it...); I don’t know where you’re getting random data from but the
>>>> chances that it’s direct from a TRNG are negligible.
>>> Normally
>>>     dd if=/dev/urandom of=$BIGRANDOM count=1024 bs=1M
>>> or in pascal
>>> var
>>>      randomsource : file of byte;
>>>      x: Integer;
>>> begin
>>>      try
>>>         assign(randomsource, '/dev/urandom');
>>>         reset(randomsource);
>>>         for x:= 1 to shuflecount do
>>>            read(randomsource, BigData[Index, x]);
>>>      finally
>>>         close(randomsource);
>>>      end;
>>> end;
>>
>>    MIGHT not be as "random" as you hope. This has LONG been a problem.
> 
> Nonsense. It’s at least as random as Carlos or I hope. Read some
> documentation for once.

   All the docs I've ever read FRET about how 'random'
   number generators aren't QUITE random enough for
   everyone to feel good.

   Now for the 99.999% of us it really isn't going to
   be a problem. However for top national security
   entities ......

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#90642 — Re: Overwriting with random data

FromCharlie Gibbs <cgibbs@kltpzyxm.invalid>
Date2026-08-26 18:08 +0000
SubjectRe: Overwriting with random data
Message-ID<UYFjS.152$oQ_6.80@fx11.iad>
In reply to#90577
On 2026-08-26, c186282 <c186282@nnada.net> wrote:

>    All the docs I've ever read FRET about how 'random'
>    number generators aren't QUITE random enough for
>    everyone to feel good.
>
>    Now for the 99.999% of us it really isn't going to
>    be a problem. However for top national security
>    entities ......

    The generation of random numbers
    is too important to be left to chance.
      -- Robert R. Coveyou

-- 
/~\  Charlie Gibbs                  |  In this world there are
\ /  <cgibbs@kltpzyxm.invalid>      |  two kinds of people:
 X   I'm really at ac.dekanfrus     |  1. Those who can extrapolate
/ \  if you read it the right way.  |  from incomplete data.

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#90506 — Re: Overwriting with random data

From"Carlos E.R." <robin_listas@es.invalid>
Date2026-08-25 11:36 +0200
SubjectRe: Overwriting with random data
Message-ID<4a40mmx4l5.ln2@Telcontar.valinor>
In reply to#90495
On 2026-08-25 08:39, c186282 wrote:
> On 8/24/26 16:26, Carlos E.R. wrote:
>> On 2026-08-24 21:57, Richard Kettlewell wrote:
>>> "Carlos E.R." <robin_listas@es.invalid> writes:
>>>> Using true random data is slow, specially if the disk or partition is
>>>> very big. Depends on how fast can the machine create new random data
>>>> (see man random and urandom). So I do tricks to do it faster.
>>>
>>> With very few exceptions nobody uses true random[1] data directly.
>>> /dev/random is a DRBG seeded from the random sources the kernel finds;
>>> shred sees its internal RNG with 32 bytes from the kernel (strace
>>> it...); I don’t know where you’re getting random data from but the
>>> chances that it’s direct from a TRNG are negligible.
>>
>> Normally
>>
>>    dd if=/dev/urandom of=$BIGRANDOM count=1024 bs=1M
>>
>> or in pascal
>>
>> var
>>     randomsource : file of byte;
>>     x: Integer;
>> begin
>>     try
>>        assign(randomsource, '/dev/urandom');
>>        reset(randomsource);
>>        for x:= 1 to shuflecount do
>>           read(randomsource, BigData[Index, x]);
>>     finally
>>        close(randomsource);
>>     end;
>> end;
> 
>    MIGHT not be as "random" as you hope. This has
>    LONG been a problem.

Sure.

Right now I have the doubt if I should have used /dev/random instead (I 
never remember which is which). But it is not that important.

> 
>    Rather than rely on some canned function, DO add
>    some shit from very transient machine-related vars
>    as well. Video vars, CPU temps, that kind of shit.
>    STILL not really truly "random" - but a lot closer.
> 
>    If you want TRUE "random", I suspect some kind of
>    little quantum device will be needed.

it is true random in the sense that the kernel provides it as random. 
That is enough.

The kernel provides two sources: one that waits if there is not enough 
random data, and the other that doesn't wait and provides what it can. I 
call the former "true random". More true random I consider unobtainium 
and go without.


> 
>>>
>>> [1] in the sense described by
>>>      e.g. https://link.springer.com/content/ 
>>> pdf/10.1007/978-3-540-85053-3_10.pdf
>>>
> 


-- 
Cheers, Carlos.
ES🇪🇸, EU🇪🇺;

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#90538 — Re: Overwriting with random data

FromRichard Kettlewell <invalid@invalid.invalid>
Date2026-08-25 15:19 +0100
SubjectRe: Overwriting with random data
Message-ID<wwvtsoimgeo.fsf@LkoBDZeT.terraraq.uk>
In reply to#90506
"Carlos E.R." <robin_listas@es.invalid> writes:
> The kernel provides two sources: one that waits if there is not enough
> random data, and the other that doesn't wait and provides what it
> can.

/dev/random and /dev/urandom are functionally equivalent today;
disregarding some details about system startup which don’t apply to most
use caes, neither will block.

> I call the former "true random". More true random I consider
> unobtainium and go without.

“True random” means something different, you need to change your
terminology.

-- 
https://www.greenend.org.uk/rjk/

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#90602 — Re: Overwriting with random data

Fromc186282 <c186282@nnada.net>
Date2026-08-26 03:33 -0400
SubjectRe: Overwriting with random data
Message-ID<shWdncVO7NhkCxP3nZ2dnZfqnPoAAAAA@giganews.com>
In reply to#90538
On 8/25/26 10:19, Richard Kettlewell wrote:
> "Carlos E.R." <robin_listas@es.invalid> writes:
>> The kernel provides two sources: one that waits if there is not enough
>> random data, and the other that doesn't wait and provides what it
>> can.
> 
> /dev/random and /dev/urandom are functionally equivalent today;
> disregarding some details about system startup which don’t apply to most
> use caes, neither will block.
> 
>> I call the former "true random". More true random I consider
>> unobtainium and go without.
> 
> “True random” means something different, you need to change your
> terminology.

   Yep. "Random" is still kind of unobtanium.

   Though only the top-level crypto people
   worry about it very much.

   "Damned-near Random" can be had quite
   easily.

   TRUE 'random' ... not even sure quantum trix
   can deliver that. Quantum is statistical, which
   narrows-down potential options. People with a
   lot of CPU might take advantage.

   The universe doesn't seem to like TRUE "random".

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#90614 — Re: Overwriting with random data

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-08-26 09:18 +0100
SubjectRe: Overwriting with random data
Message-ID<116m7h8$e9qm$6@dont-email.me>
In reply to#90602
On 26/08/2026 08:33, c186282 wrote:

> 
>    TRUE 'random' ... not even sure quantum trix
>    can deliver that. Quantum is statistical, which
>    narrows-down potential options. People with a
>    lot of CPU might take advantage.
> 
>    The universe doesn't seem to like TRUE "random".
> 
Thermal and shot noise are true random, and are used to generate  random 
numbers


-- 
All political activity makes complete sense once the proposition that 
all government is basically a self-legalising protection racket, is 
fully understood.

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#90637 — Re: Overwriting with random data

Fromrbowman <bowman@montana.com>
Date2026-08-26 17:34 +0000
SubjectRe: Overwriting with random data
Message-ID<nf8mdtFprcuU4@mid.individual.net>
In reply to#90614
On Wed, 26 Aug 2026 09:18:48 +0100, The Natural Philosopher wrote:

> Thermal and shot noise are true random, and are used to generate  random
> numbers

https://hackaday.io/project/21054-true-random-number-generator

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#90519 — Re: Overwriting with random data

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-08-25 12:12 +0100
SubjectRe: Overwriting with random data
Message-ID<116jta2$3l7js$9@dont-email.me>
In reply to#90495
On 25/08/2026 07:39, c186282 wrote:
> If you want TRUE "random", I suspect some kind of
>    little quantum device will be needed.

Run a Zener diodes amplified output through an A to D converter.
That's quantum...

-- 
“it should be clear by now to everyone that activist environmentalism 
(or environmental activism) is becoming a general ideology about humans, 
about their freedom, about the relationship between the individual and 
the state, and about the manipulation of people under the guise of a 
'noble' idea. It is not an honest pursuit of 'sustainable development,' 
a matter of elementary environmental protection, or a search for 
rational mechanisms designed to achieve a healthy environment. Yet 
things do occur that make you shake your head and remind yourself that 
you live neither in Joseph Stalin’s Communist era, nor in the Orwellian 
utopia of 1984.”

Vaclav Klaus

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#90587 — Re: Overwriting with random data

Fromc186282 <c186282@nnada.net>
Date2026-08-26 00:09 -0400
SubjectRe: Overwriting with random data
Message-ID<ZfqcnXZt_dTR-hP3nZ2dnZfqnPWdnZ2d@giganews.com>
In reply to#90519
On 8/25/26 07:12, The Natural Philosopher wrote:
> On 25/08/2026 07:39, c186282 wrote:
>> If you want TRUE "random", I suspect some kind of
>>    little quantum device will be needed.
> 
> Run a Zener diodes amplified output through an A to D converter.
> That's quantum...

   Pretty much, theoretically. Tunnel diodes might
   be exploited in a similar fashion. Anything where
   'quantum noise' gets involved.

   Anyway, STILL hear paranoia from the "Top People"
   about pseudo-random numbers for hard core crypto.
   For most of us it's not really a thing, but at
   the very high/secret levels ... stuff evil players
   will invest millions/billions into cracking ....

   Oh, even quantum obeys some statistical rules,
   on a larger scale states/events ARE kinda
   constrained. IF you can put enough CPU/AI on
   the case it could narrow down the best attacks
   on crypto systems.

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#90606 — Re: Overwriting with random data

FromThe Natural Philosopher <tnp@invalid.invalid>
Date2026-08-26 08:52 +0100
SubjectRe: Overwriting with random data
Message-ID<116m60p$e9qm$2@dont-email.me>
In reply to#90587
On 26/08/2026 05:09, c186282 wrote:
> On 8/25/26 07:12, The Natural Philosopher wrote:
>> On 25/08/2026 07:39, c186282 wrote:
>>> If you want TRUE "random", I suspect some kind of
>>>    little quantum device will be needed.
>>
>> Run a Zener diodes amplified output through an A to D converter.
>> That's quantum...
> 
>    Pretty much, theoretically. Tunnel diodes might
>    be exploited in a similar fashion. Anything where
>    'quantum noise' gets involved.
> 

TBH  any noise source - even thermal noise - can be used


-- 
“It is hard to imagine a more stupid decision or more dangerous way of 
making decisions than by putting those decisions in the hands of people 
who pay no price for being wrong.”

Thomas Sowell

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