Re: /dev/tcp

From	"Carlos E.R." <robin_listas@es.invalid>
Newsgroups	comp.os.linux.misc
Subject	Re: /dev/tcp
Date	2026-08-24 09:45 +0200
Organization	Tebibyte_Retro_Gaming
Message-ID	<jd9tlmxhcg.ln2@Telcontar.valinor> (permalink)
References	(6 earlier) <116dggf$1idoq$1@dont-email.me> <116draf$1ktfi$2@dont-email.me> <5b2dnb6l8sPvPhf3nZ2dnZfqnPGdnZ2d@giganews.com> <6d3rlmxqg4.ln2@Telcontar.valinor> <ViCdnRVVJp6KVBb3nZ2dnZfqnPudnZ2d@giganews.com>

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On 2026-08-24 06:31, c186282 wrote:
> On 8/23/26 07:50, Carlos E.R. 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:


>>>    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.
> 
>    Um ... how many GB could that cope with ?

I have done entire disks sized terabytes. But I don't actually use "seek".

> 
>    'Seek' counts can sometimes be supplimented
>    by an 'offset' value - so basically you're
>    getting the mult of two doubles. I didn't
>    do it that way, and thus needed very large
>    sector/track/cluster integers. An external 'C'
>    pgm using really large integer types was needed.

Can you seek not a byte, but a record or array?

Seek(var F; N: Int64)

File can be a file of some variable that is not a byte. And

type Int64 = - 9223372036854775808..9223372036854775807;

(why signed?)

Why not QWord?

type QWord = 0..18446744073709551615;


>    Anyway, it worked.
> 
>    My app could ALSO just LOOK at data, kinda put
>    it into a "ghex"-looking sidebar (but with
>    ASCII translation if possible). So you could
>    just look, OR zap. Anyway, nothing TOO complex
>    aside from the sheer size of modern mag disks.
> 
>    As useful utility. I encourage people to write
>    their own.
> 
>    DID add one odd, maybe questionable, feature ...
>    you could spec on the CL x-number of gigs to
>    TOTALLY wipe at the beginning ... and then
>    a couple numbers for "shotgun" blasting of
>    later tracks. Most of the file-table/system
>    stuff tends to be early on, and data with
>    holes in it is "less useful". This made the
>    "wipes" much faster.
> 


-- 
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: 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: /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: 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: /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

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