Name
mtools - utilities to access DOS disks in Unix.
Introduction
Mtools is a public domain collection of tools to allow Unix
systems to manipulate MS-DOS files: read, write, and move
around files on an MS-DOS filesystem (typically a floppy
disk). Where reasonable, each program attempts to emulate
the MS-DOS equivalent command. However, unnecessary restric-
tions and oddities of DOS are not emulated. For instance, it
is possible to move subdirectories from one subdirectory to
another.
Mtools is sufficient to give access to MS-DOS filesystems.
For instance, commands such as mdir a: work on the a: floppy
without any preliminary mounting or initialization (assuming
the default `/etc/mtools.conf' works on your machine). With
mtools, one can change floppies too without unmounting and
mounting.
Where to get mtools
Mtools can be found at the following places (and their mir-
rors):
http://mtools.linux.lu/mtools-3.9.7.tar.gz
ftp://www.tux.org/pub/knaff/mtools/mtools-3.9.7.tar.gz
ftp://metalab.unc.edu/pub/Linux/utils/disk-management/mtools-3.9.7.tar.gz
Before reporting a bug, make sure that it has not yet been
fixed in the Alpha patches which can be found at:
http://mtools.linux.lu/
ftp://www.tux.org/pub/knaff/mtools
These patches are named mtools-version-ddmm.taz, where ver-
sion stands for the base version, dd for the day and mm for
the month. Due to a lack of space, I usually leave only the
most recent patch.
There is an mtools mailing list at mtools @ tux.org .
Please send all bug reports to this list. You may subscribe
to the list by sending a message with 'subscribe mtools @
tux.org' in its body to majordomo @ tux.org . (N.B. Please
remove the spaces around the "@" both times. I left them
there in order to fool spambots.) Announcements of new
mtools versions will also be sent to the list, in addition
to the linux announce newsgroups. The mailing list is
archived at http://www.tux.org/hypermail/mtools/latest
Common features of all mtools commands
Options and filenames
MS-DOS filenames are composed of a drive letter followed by
a colon, a subdirectory, and a filename. Only the filename
part is mandatory, the drive letter and the subdirectory are
optional. Filenames without a drive letter refer to Unix
files. Subdirectory names can use either the '/' or '\'
separator. The use of the '\' separator or wildcards
requires the names to be enclosed in quotes to protect them
from the shell. However, wildcards in Unix filenames should
not be enclosed in quotes, because here we want the shell to
expand them.
The regular expression "pattern matching" routines follow
the Unix-style rules. For example, `*' matches all MS-DOS
files in lieu of `*.*'. The archive, hidden, read-only and
system attribute bits are ignored during pattern matching.
All options use the - (minus) as their first character, not
/ as you'd expect in MS-DOS.
Most mtools commands allow multiple filename parameters,
which doesn't follow MS-DOS conventions, but which is more
user-friendly.
Most mtools commands allow options that instruct them how to
handle file name clashes. See section name clashes, for more
details on these. All commands accept the -V flags which
prints the version, and most accept the -v flag, which
switches on verbose mode. In verbose mode, these commands
print out the name of the MS-DOS files upon which they act,
unless stated otherwise. See section Commands, for a
description of the options which are specific to each com-
mand.
Drive letters
The meaning of the drive letters depends on the target
architectures. However, on most target architectures, drive
A is the first floppy drive, drive B is the second floppy
drive (if available), drive J is a Jaz drive (if available),
and drive Z is a Zip drive (if available). On those systems
where the device name is derived from the SCSI id, the Jaz
drive is assumed to be at Scsi target 4, and the Zip at Scsi
target 5 (factory default settings). On Linux, both drives
are assumed to be the second drive on the Scsi bus
(/dev/sdb). The default settings can be changes using a con-
figuration file (see section Configuration).
Current working directory
The mcd command (`mcd') is used to establish the device and
the current working directory (relative to the MS-DOS
filesystem), otherwise the default is assumed to be A:/.
However, unlike MS-DOS, there is only one working directory
for all drives, and not one per drive.
VFAT-style long file names
This version of mtools supports VFAT style long filenames.
If a Unix filename is too long to fit in a short DOS name,
it is stored as a VFAT long name, and a companion short name
is generated. This short name is what you see when you exam-
ine the disk with a pre-7.0 version of DOS.
The following table shows some examples of short names:
Long name MS-DOS name Reason for the change
--------- ---------- ---------------------
thisisatest THISIS~1 filename too long
alain.knaff ALAIN~1.KNA extension too long
prn.txt PRN~1.TXT PRN is a device name
.abc ABC~1 null filename
hot+cold HOT_CO~1 illegal character
As you see, the following transformations happen to derive
a short name:
* Illegal characters are replaced by underscores. The
illegal characters are ;+=[]',\"*\\<>/?:|.
* Extra dots, which cannot be interpreted as a main
name/extension separator are removed
* A ~n number is generated,
* The name is shortened so as to fit in the 8+3 limita-
tion
The initial Unix-style file name (whether long or short) is
also called the primary name, and the derived short name is
also called the secondary name.
Example:
mcopy /etc/motd a:Reallylongname
Mtools creates a VFAT entry for Reallylongname, and uses
REALLYLO as a short name. Reallylongname is the primary
name, and REALLYLO is the secondary name.
mcopy /etc/motd a:motd
Motd fits into the DOS filename limits. Mtools doesn't need
to derivate another name. Motd is the primary name, and
there is no secondary name.
In a nutshell: The primary name is the long name, if one
exists, or the short name if there is no long name.
Although VFAT is much more flexible than FAT, there are
still names that are not acceptable, even in VFAT. There are
still some illegal characters left (\"*\\<>/?:|), and device
names are still reserved.
Unix name Long name Reason for the change
--------- ---------- ---------------------
prn prn-1 PRN is a device name
ab:c ab_c-1 illegal character
As you see, the following transformations happen if a long
name is illegal:
* Illegal characters are replaces by underscores,
* A -n number is generated,
Name clashes
When writing a file to disk, its long name or short name may
collide with an already existing file or directory. This may
happen for all commands which create new directory entries,
such as mcopy, mmd, mren, mmove, mwrite and mread. When a
name clash happens, mtools asks you what it should do. It
offers several choices:
overwrite
Overwrites the existing file. It is not possible to
overwrite a directory with a file.
rename
Renames the newly created file. Mtools prompts for the
new filename
autorename
Renames the newly created file. Mtools chooses a name
by itself, without prompting
skip
Gives up on this file, and moves on to the next (if
any)
To chose one of these actions, type its first letter at the
prompt. If you use a lower case letter, the action only
applies for this file only, if you use an upper case letter,
the action applies to all files, and you won't be prompted
again.
You may also chose actions (for all files) on the command
line, when invoking mtools:
-D o
Overwrites primary names by default.
-D O
Overwrites secondary names by default.
-D r
Renames primary name by default.
-D R
Renames secondary name by default.
-D a
Autorenames primary name by default.
-D A
Autorenames secondary name by default.
-D s
Skip primary name by default.
-D S
Skip secondary name by default.
-D m
Ask user what to do with primary name.
-D M
Ask user what to do with secondary name.
Note that for command line switches lower/upper differen-
tiates between primary/secondary name whereas for interac-
tive choices, lower/upper differentiates between just-this-
time/always.
The primary name is the name as displayed in Windows 95 or
Windows NT: i.e. the long name if it exists, and the short
name otherwise. The secondary name is the "hidden" name,
i.e. the short name if a long name exists.
By default, the user is prompted if the primary name
clashes, and the secondary name is autorenamed.
If a name clash occurs in a Unix directory, mtools only asks
whether to overwrite the file, or to skip it.
Case sensitivity of the VFAT filesystem
The VFAT filesystem is able to remember the case of the
filenames. However, filenames which differ only in case are
not allowed to coexist in the same directory. For example if
you store a file called LongFileName on a VFAT filesystem,
mdir shows this file as LongFileName, and not as Long-
filename. However, if you then try to add LongFilename to
the same directory, it is refused, because case is ignored
for clash checks.
The VFAT filesystem allows to store the case of a filename
in the attribute byte, if all letters of the filename are
the same case, and if all letters of the extension are the
same case too. Mtools uses this information when displaying
the files, and also to generate the Unix filename when
mcopying to a Unix directory. This may have unexpected
results when applied to files written using an pre-7.0 ver-
sion of DOS: Indeed, the old style filenames map to all
upper case. This is different from the behavior of the old
version of mtools which used to generate lower case Unix
filenames.
high capacity formats
Mtools supports a number of formats which allow to store
more data on disk as usual. Due to different operating sys-
tem abilities, these formats are not supported on all OS'es.
Mtools recognizes these formats transparently where sup-
ported.
In order to format these disks, you need to use an operating
system specific tool. For Linux, suitable floppy tools can
be found in the fdutils package at the following locations~:
ftp://www.tux.org/pub/knaff/fdutils/.
ftp://metalab.unc.edu/pub/Linux/utils/disk-management/fdutils-*
See the manpages included in that package for further
detail: Use superformat to format all formats except XDF,
and use xdfcopy to format XDF.
More sectors
The oldest method of fitting more data on a disk is to use
more sectors and more cylinders. Although the standard for-
mat uses 80 cylinders and 18 sectors (on a 3 1/2 high den-
sity disk), it is possible to use up to 83 cylinders (on
most drives) and up to 21 sectors. This method allows to
store up to 1743K on a 3 1/2 HD disk. However, 21 sector
disks are twice as slow as the standard 18 sector disks
because the sectors are packed so close together that we
need to interleave them. This problem doesn't exist for 20
sector formats.
These formats are supported by numerous DOS shareware utili-
ties such as fdformat and vgacopy. In his infinite hybris,
Bill Gate$ believed that he invented this, and called it
`DMF disks', or `Windows formatted disks'. But in reality,
it has already existed years before! Mtools supports these
formats on Linux, on SunOs and on the DELL Unix PC.
Bigger sectors
By using bigger sectors it is possible to go beyond the
capacity which can be obtained by the standard 512-byte sec-
tors. This is because of the sector header. The sector
header has the same size, regardless of how many data bytes
are in the sector. Thus, we save some space by using fewer,
but bigger sectors. For example, 1 sector of 4K only takes
up header space once, whereas 8 sectors of 512 bytes have
also 8 headers, for the same amount of useful data.
This method allows to store up to 1992K on a 3 1/2 HD disk.
Mtools supports these formats only on Linux.
2m
The 2m format was originally invented by Ciriaco Garcia de
Celis. It also uses bigger sectors than usual in order to
fit more data on the disk. However, it uses the standard
format (18 sectors of 512 bytes each) on the first cylinder,
in order to make these disks easyer to handle by DOS. Indeed
this method allows to have a standard sized bootsector,
which contains a description of how the rest of the disk
should be read.
However, the drawback of this is that the first cylinder can
hold less data than the others. Unfortunately, DOS can only
handle disks where each track contains the same amount of
data. Thus 2m hides the fact that the first track contains
less data by using a shadow FAT. (Usually, DOS stores the
FAT in two identical copies, for additional safety. XDF
stores only one copy, and it tells DOS that it stores two.
Thus the same that would be taken up by the second FAT copy
is saved.) This also means that your should never use a 2m
disk to store anything else than a DOS fs.
Mtools supports these format only on Linux.
XDF
XDF is a high capacity format used by OS/2. It can hold 1840
K per disk. That's lower than the best 2m formats, but its
main advantage is that it is fast: 600 milliseconds per
track. That's faster than the 21 sector format, and almost
as fast as the standard 18 sector format. In order to access
these disks, make sure mtools has been compiled with XDF
support, and set the use_xdf variable for the drive in the
configuration file. See section Compiling mtools, and `misc
variables', for details on how to do this. Fast XDF access
is only available for Linux kernels which are more recent
than 1.1.34.
Mtools supports this format only on Linux.
Caution / Attention distributors: If mtools is compiled on a
Linux kernel more recent than 1.3.34, it won't run on an
older kernel. However, if it has been compiled on an older
kernel, it still runs on a newer kernel, except that XDF
access is slower. It is recommended that distribution
authors only include mtools binaries compiled on kernels
older than 1.3.34 until 2.0 comes out. When 2.0 will be out,
mtools binaries compiled on newer kernels may (and should)
be distributed. Mtools binaries compiled on kernels older
than 1.3.34 won't run on any 2.1 kernel or later.
Exit codes
All the Mtools commands return 0 on success, 1 on utter
failure, or 2 on partial failure. All the Mtools commands
perform a few sanity checks before going ahead, to make sure
that the disk is indeed an MS-DOS disk (as opposed to, say
an ext2 or minix disk). These checks may reject partially
corrupted disks, which might otherwise still be readable. To
avoid these checks, set the MTOOLS_SKIP_CHECK environmental
variable or the corresponding configuration file variable
(see section global variables)
Bugs
An unfortunate side effect of not guessing the proper device
(when multiple disk capacities are supported) is an occa-
sional error message from the device driver. These can be
safely ignored.
The fat checking code chokes on 1.72 Mb disks mformatted
with pre-2.0.7 mtools. Set the environmental variable
MTOOLS_FAT_COMPATIBILITY (or the corresponding configuration
file variable, `global variables') to bypass the fat check-
ing.
See also
mattrib mbadblocks mcd mcopy mdel mdeltree mdir mdu mformat
mkmanifest mlabel mmd mmount mmove mrd mread mren mtoolstest
mtype
