info-mtools
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Info-mtools] What does it take to support FAT12 dialects?


From: Alain Knaff
Subject: Re: [Info-mtools] What does it take to support FAT12 dialects?
Date: Thu, 20 May 2021 00:32:20 +0200
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0

Hi,

Found it.

There are actually 2 different reasons for the 1.2M and the 2.4M image.

1. For the 1.2M image, everything is fine, but the directory entries all
have the DOS "hidden" attribute set, and hence are not shown.

To show them, use the -a flag to mdir:

> mdir  -i ~/tmp/12.img  -a ::
 Volume in drive : has no label
Directory for ::/

VOLUME   LAB       512 1991-11-22  14:26
MAINTRK  DIA     15360 1991-11-22  14:26
MRNLEV   ECN       512 1991-11-22  14:26
013179   DSL    390144 1991-11-22  14:27
003290   DSL    180224 1980-01-01   0:00
023193   DSL    157696 1980-00-00   0:00
        6 files             744 448 bytes
                            469 504 bytes free


2. For the 2.4M image, there is an actual inconsistency. The number of
"reserved" sectors (boot sectors) is set to 32, but actually only one
boot sector is used. Hence everything is shifted by 31 sectors.

Hardwiring this to 1 in init.c results in a readable directory:

> ./mdir  -i ~/tmp/24.img  -a ::
 Volume in drive : has no label
Directory for ::/

VOLUME   LAB       512 1980-00-00   0:00
PLOM     IML    179200 1980-00-00   0:00
CTLDMC0  IML    110080 1980-00-00   0:00
USCNI    IML     74638 1980-00-00   0:00
USCNI2   IML    197538 1980-00-00   0:00
CONTROL  FIL       181 1980-00-00   0:00
PIT      TBL     64892 1980-00-00   0:00
HOST     PUR      6058 1980-00-00   0:00
SAMOA    PUR     27606 1980-00-00   0:00
SAMOAA   PUR     26776 1980-00-00   0:00
APPNODE  PUR     28023 1980-00-00   0:00
LOC      PUR       128 1980-00-00   0:00
FILTR    PUR      2937 1980-00-00   0:00
WAN      PUR       564 1980-00-00   0:00
APPNCOS  PUR      6524 1980-00-00   0:00
DVD      PUR      6943 1980-00-00   0:00
PAST     PUR     22712 1980-00-00   0:00
AEASTATN PUR      4474 1980-00-00   0:00
AEAOTHER PUR     19533 1980-00-00   0:00
TCPIP    PUR      1330 1980-00-00   0:00
CTLPAT   PUR       480 1980-00-00   0:00
RPQ      PUR       220 1980-00-00   0:00
SSDACONF OPR     13312 1980-00-00   0:00
CDID     DIA      1920 1980-00-00   0:00
COPYCTL  DUM       728 1980-00-00   0:00
MODKEYBD KDU     18432 1980-00-00   0:00
RASDATA  OPR     30720 1980-00-00   0:00
RASDATAM OPR     30720 1980-00-00   0:00
LINKMAP  IML      5120 1980-00-00   0:00
LINKMA51 IML      4096 1980-00-00   0:00
LINKMA52 IML      4096 1980-00-00   0:00
SAFSTOR  STA       512 1980-00-00   0:00
MAINTEC  MEC       662 1980-00-00   0:00
PATCH001 CUT      6144 1980-00-00   0:00
LEOTF    IML   1048576 1980-00-00   0:00
TRSETUP  OPR      2168 1980-00-00   0:00
VPDDATA  FIL      5874 1980-00-00   0:00
UDDDATA  FIL     13900 1980-00-00   0:00
SIOA     AML     47616 1980-00-00   0:00
CSCMBSL  IML      1024 1980-00-00   0:00
FCSCMBSL IML       512 1980-00-00   0:00
MSFPID   DAT       345 1980-00-00   0:00
PCB38E3  PAT       512 1980-00-00   0:00
       43 files           2 018 338 bytes
                            407 552 bytes free

In the next few days, I'll make a release that adds a flag to optionally
ignore the number of boot sectors, and always use 1

Regards,

Alain



reply via email to

[Prev in Thread] Current Thread [Next in Thread]