Re: /dev/tcp

From	"Carlos E.R." <robin_listas@es.invalid>
Newsgroups	comp.os.linux.misc
Subject	Re: /dev/tcp
Date	2026-08-23 13:50 +0200
Organization	Tebibyte_Retro_Gaming
Message-ID	<6d3rlmxqg4.ln2@Telcontar.valinor> (permalink)
References	(4 earlier) <eli$2608201414@qaz.wtf> <11682mv$3s8jk$7@dont-email.me> <116dggf$1idoq$1@dont-email.me> <116draf$1ktfi$2@dont-email.me> <5b2dnb6l8sPvPhf3nZ2dnZfqnPGdnZ2d@giganews.com>

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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🇪🇺;

Thread

/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 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: /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 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> - 2026-08-24 00:53 -0400
                Re: The hammer is best rbowman <bowman@montana.com> - 2026-08-24 06:42 +0000
                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> - 2026-08-23 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: /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

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