Re: Base85 for DOS

On Sat, 24 Aug 2024 08:38:48 +0100, Kerr-Mudd, John <admin@127.0.0.1>  wrote:

On Fri, 23 Aug 2024 23:00:32 +0200
wolfgang kern <nowhere@never.at> wrote:
>

On 23/08/2024 21:17, Kerr-Mudd, John wrote:
...

back then (~1984..) there were several tools available.
I wrote one 1985  as a DOS-extender,
but we had no internet so it was never published.
you may find a lot of later attempts from many sources now:
"HEX2BIN" or similar names with .ASM,.OBJ,.COM or even .EXE.

>

this task is/was that easy and short...
so whenever needed this few bytes can be written any time.

>

The 'problem' with debug output is that it has address prefixes and
display values at the end that need stripping out to get pure hex.

>
depending on file size limits part of the address field may be useful,
and the ASCII trail were just ignored by hex2bin.

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You have to code for it, or maybe you'd pick up displayed valid hex codes
>

>

I could post code in hex, if that's more acceptable - it's just easier
for me to just CnP a debug dump.

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your style is readable for me (after eye recovers from wrong treatment).
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I did hex2bin and v versa a while back; OK I'll revisit it to have a
prog that does both.

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AFAIR early DOS had debug.com, later vsn debug.exe.
hex_dump options were a bit different.

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My xxd-r allows for both grdb and debug.exe dumps. I haven't tested it
under earlier DOS versions with possibly different dump format.
>

>
my OS contains only bin2hex as part of the implied debug+disass.
the address field vary with the chosen range and always show ASCII:

:           1         2         3         4         5         6

0123456789012345678901234567890123456789012345678901234567890123456789
xxxx_xxxx 00 01 02 03 04 05 06 07  08 09 0a 0b 0c 0d 0e 0f 8+1+8 chars.
so line length is 71 or 76 which fit into 80 char screens and .nws too.

I think xxd-r should handle that; it relies on there being 16 (hex pairs
+blank) +1 per line. Hmm, I should count pairs, not cols.
>

My latest won't cater for that format; it assumes that a double space  implies end of hex pairs; it would fail in the middle of your output.
Counting down pairs might be better, but needs more coding to handle a  short line at the end.
--
Bah, and indeed, Humbug