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Name
mtools.conf - mtools configuration files
Description
This manual page describes the configuration files for mtools. They
are called `/usr/local/etc/mtools.conf' and `~/.mtoolsrc'. If the
environmental variable MTOOLSRC is set, its contents is used as the
filename for a third configuration file. These configuration files
describe the following items:
* Global configuration flags and variables
* Per drive flags and variables
Location of the configuration files
`/usr/local/etc/mtools.conf' is the system-wide configuration file,
and `~/.mtoolsrc' is the user's private configuration file.
On some systems, the system-wide configuration file is called
`/etc/default/mtools.conf' instead.
General configuration file syntax
The configuration files is made up of sections. Each section starts
with a keyword identifying the section followed by a colon. Then
follow variable assignments and flags. Variable assignments take the
following form:
name=value
Flags are lone keywords without an equal sign and value following
them. A section either ends at the end of the file or where the next
section begins.
Lines starting with a hash (#) are comments. Newline characters are
equivalent to whitespace (except where ending a comment). The
configuration file is case insensitive, except for item enclosed in
quotes (such as filenames).
Default values
For most platforms, mtools contains reasonable compiled-in defaults
for physical floppy drives. Thus, you usually don't need to bother
with the configuration file, if all you want to do with mtools is to
access your floppy drives. On the other hand, the configuration file
is needed if you also want to use mtools to access your hard disk
partitions and DOSEMU image files.
Global variables
Global flags may be set to 1 or to 0.
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The following global flags are recognized:
MTOOLS_SKIP_CHECK
If this is set to 1, mtools skips most of its sanity checks. This
is needed to read some Atari disks which have been made with the
earlier ROMs, and which would not be recognized otherwise.
MTOOLS_FAT_COMPATIBILITY
If this is set to 1, mtools skips the fat size checks. Some disks
have a bigger FAT than they really need to. These are rejected if
this option is not set.
MTOOLS_LOWER_CASE
If this is set to 1, mtools displays all-upper-case short
filenames as lowercase. This has been done to allow a behavior
which is consistent with older versions of mtools which didn't
know about the case bits.
MTOOLS_NO_VFAT
If this is set to 1, mtools won't generate VFAT entries for
filenames which are mixed-case, but otherwise legal dos
filenames. This is useful when working with DOS versions which
can't grok VFAT long names, such as FreeDOS.
MTOOLS_DOTTED_DIR
In a wide directory, prints the short name with a dot instead of
spaces separating the basename and the extension.
MTOOLS_NAME_NUMERIC_TAIL
If this is set to one (default), generate numeric tails for all
long names (~1). If set to zero, only generate numeric tails if
otherwise a clash would have happened.
MTOOLS_TWENTY_FOUR_HOUR_CLOCK
If 1, uses the European notation for times (twenty four hour
clock), else uses the UK/US notation (am/pm)
MTOOLS_LOCK_TIMEOUT
How long, in seconds, to wait for a locked device to become free.
Defaults to 30.
Example: Inserting the following line into your configuration file
instructs mtools to skip the sanity checks:
MTOOLS_SKIP_CHECK=1
Global variables may also be set via the environment:
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export MTOOLS_SKIP_CHECK=1
Global string variables may be set to any value:
MTOOLS_DATE_STRING
The format used for printing dates of files. By default, is dd-
mm-yyyy.
Per drive flags and variables
General information
Per drive flags and values may be described in a drive section. A
drive section starts with drive "driveletter" :
Then follow variable-value pairs and flags.
This is a sample drive description:
drive a:
file="/dev/fd0" use_xdf=1
Location information
For each drive, you need to describe where its data is physically
stored (image file, physical device, partition, offset).
file
The name of the file or device holding the disk image. This is
mandatory. The file name should be enclosed in quotes.
partition
Tells mtools to treat the drive as a partitioned device, and to
use the given partition. Only primary partitions are accessible
using this method, and they are numbered from 1 to 4. For logical
partitions, use the more general offset variable. The partition
variable is intended for removable media such as Syquest disks,
ZIP drives, and magneto-optical disks. Although traditional DOS
sees Syquest disks and magneto-optical disks as `giant floppy
disks' which are unpartitioned, OS/2 and Windows NT treat them
like hard disks, i.e. partitioned devices. The partition flag is
also useful DOSEMU hdimages. It is not recommended for hard disks
for which direct access to partitions is available through
mounting.
offset
Describes where in the file the MS-DOS file system starts. This
is useful for logical partitions in DOSEMU hdimages, and for
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ATARI ram disks. By default, this is zero, meaning that the file
system starts right at the beginning of the device or file.
Disk Geometry Configuration
Geometry information describes the physical characteristics about the
disk. Its has three purposes:
formatting
The geometry information is written into the boot sector of the
newly made disk. However, you may also describe the geometry
information on the command line. See section mformat, for
details.
filtering
On some Unixes there are device nodes which only support one
physical geometry. For instance, you might need a different node
to access a disk as high density or as low density. The geometry
is compared to the actual geometry stored on the boot sector to
make sure that this device node is able to correctly read the
disk. If the geometry doesn't match, this drive entry fails, and
the next drive entry bearing the same drive letter is tried. See
section multiple descriptions, for more details on supplying
several descriptions for one drive letter.
If no geometry information is supplied in the configuration file,
all disks are accepted. On Linux (and on SPARC) there exist
device nodes with configurable geometry (`/dev/fd0', `/dev/fd1'
etc), and thus filtering is not needed (and ignored) for disk
drives. (Mtools still does do filtering on plain files (disk
images) in Linux: this is mainly intended for test purposes, as I
don't have access to a Unix which would actually need filtering).
If you do not need filtering, but want still a default geometry
for mformatting, you may switch off filtering using the
mformat_only flag.
If you want filtering, you should supply the filter flag. If you
supply a geometry, you must supply one of both flags.
initial geometry
On devices that support it (usually floppy devices), the geometry
information is also used to set the initial geometry. This
initial geometry is applied while reading the boot sector, which
contains the real geometry. If no geometry information is
supplied in the configuration file, or if the mformat_only flag
is supplied, no initial configuration is done.
On Linux, initial geometry is not really needed, as the
configurable devices are able to auto-detect the disk type
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accurately enough (for most common formats) to read the boot
sector.
Wrong geometry information may lead to very bizarre errors. That's why
I strongly recommend that you add the mformat_only flag to your drive
description, unless you really need filtering or initial geometry.
The following geometry related variables are available:
cylinders
tracks
The number of cylinders. (cylinders is the preferred form, tracks
is considered obsolete)
heads
The number of heads (sides).
sectors
The number of sectors per track.
Example: the following drive section describes a 1.44M drive:
drive a:
file="/dev/fd0H1440"
fat_bits=12
cylinders=80 heads=2 sectors=18
mformat_only
The following shorthand geometry descriptions are available:
1.44m
high density 3 1/2 disk. Equivalent to: fat_bits=12 cylinders=80
heads=2 sectors=18
1.2m
high density 5 1/4 disk. Equivalent to: fat_bits=12 cylinders=80
heads=2 sectors=15
720k
double density 3 1/2 disk. Equivalent to: fat_bits=12
cylinders=80 heads=2 sectors=9
360k
double density 5 1/4 disk. Equivalent to: fat_bits=12
cylinders=40 heads=2 sectors=9
The shorthand format descriptions may be amended. For example, 360k
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sectors=8 describes a 320k disk and is equivalent to: fat_bits=12
cylinders=40 heads=2 sectors=8
Open Flags
Moreover, the following flags are available:
sync
All i/o operations are done synchronously
nodelay
The device or file is opened with the O_NDELAY flag. This is
needed on some non-Linux architectures.
exclusive
The device or file is opened with the O_EXCL flag. On Linux, this
ensures exclusive access to the floppy drive. On most other
architectures, and for plain files it has no effect at all.
General Purpose Drive Variables
The following general purpose drive variables are available.
Depending to their type, these variables can be set to a string
(precmd, postcmd) or an integer (all others)
fat_bits
The number of FAT bits. This may be 12 or 16. This is very rarely
needed, as it can almost always be deduced from information in
the boot sector. On the contrary, describing the number of fat
bits may actually be harmful if you get it wrong. You should only
use it if mtools gets the auto-detected number of fat bits wrong,
or if you want to mformat a disk with a weird number of fat bits.
codepage
Describes the DOS code page used for short filenames. This is a
number between 1 and 999. By default, code page 850 is used. The
reason for this is because this code page contains most of the
characters that are also available in ISO-Latin-1. You may also
specify a global code page for all drives by using the global
default_codepage parameter (outside of any drive description).
This parameters exists starting at version 4.0.0
data_map
Remaps data from image file. This is useful for image files which
might need additional zero-filled sectors to be inserted. Such is
the case for instance for IBM 3174 floppy images. These images
represent floppy disks with fewer sectors on their first
cylinder. These missing sectors are not stored in the image, but
are still counted in the filesystem layout. The data_map allows
to fake these missing sectors for the upper layers of mtools. A
data_map is a comma-separated sequence of source type and size.
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Source type may be zero for zero-filled sectors created by map,
skip for data in raw image to be ignored (skipped), and nothing
for data to be used as is (copied) from the raw image. Datamap is
automatically complemented by an implicit last element of data to
be used as is from current offset to end of file. Each size is a
number followed by a unit: s for a 512 byte sector, K for Kbytes,
M for megabytes, G for gigabytes, and nothing for single bytes.
Example:
data_map=1s,zero31s,28s,skip1s would be a map for use with IBM
3174 floppy images. First sector (1s, boot sector) is used as is.
Then follow 31 fake zero-filled sectors (zero31s), then the next
28 sectors from image (28s) are used as is (they contain FAT and
root directory), then one sector from image is skipped (skip1s),
and finally the rest of image is used as is (implicit)
precmd
Executes the given command before opening the device. On some
variants of Solaris, it is necessary to call 'volcheck -v' before
opening a floppy device, in order for the system to notice that
there is indeed a disk in the drive. precmd="volcheck -v" in the
drive clause establishes the desired behavior.
postcmd
Executes the given command after closing the device. May be
useful if mtools shares the image file with some other
application, in order to release the image file to that
application.
blocksize
This parameter represents a default block size to be always used
on this device. All I/O is done with multiples of this block
size, independently of the sector size registered in the file
system's boot sector. This is useful for character devices whose
sector size is not 512, such as for example CD-ROM drives on
Solaris.
Only the file variable is mandatory. The other parameters may be left
out. In that case a default value or an auto-detected value is used.
General Purpose Drive Flags
A flag can either be set to 1 (enabled) or 0 (disabled). If the value
is omitted, it is enabled. For example, scsi is equivalent to scsi=1
nolock
Instruct mtools to not use locking on this drive. This is needed
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on systems with buggy locking semantics. However, enabling this
makes operation less safe in cases where several users may access
the same drive at the same time.
scsi
When set to 1, this option tells mtools to use raw SCSI I/O
instead of the standard read/write calls to access the device.
Currently, this is supported on HP-UX, Solaris and SunOS. This
is needed because on some architectures, such as SunOS or
Solaris, PC media can't be accessed using the read and write
system calls, because the OS expects them to contain a Sun
specific "disk label".
As raw SCSI access always uses the whole device, you need to
specify the "partition" flag in addition
On some architectures, such as Solaris, mtools needs root
privileges to be able to use the scsi option. Thus mtools should
be installed setuid root on Solaris if you want to access Zip/Jaz
drives. Thus, if the scsi flag is given, privileged is
automatically implied, unless explicitly disabled by privileged=0
Mtools uses its root privileges to open the device, and to issue
the actual SCSI I/O calls. Moreover, root privileges are only
used for drives described in a system-wide configuration file
such as `/usr/local/etc/mtools.conf', and not for those described
in `~/.mtoolsrc' or `$MTOOLSRC'.
privileged
When set to 1, this instructs mtools to use its setuid and setgid
privileges for opening the given drive. This option is only
valid for drives described in the system-wide configuration files
(such as `/usr/local/etc/mtools.conf', not `~/.mtoolsrc' or
`$MTOOLSRC'). Obviously, this option is also a no op if mtools
is not installed setuid or setgid. This option is implied by
'scsi=1', but again only for drives defined in system-wide
configuration files. Privileged may also be set explicitly to 0,
in order to tell mtools not to use its privileges for a given
drive even if scsi=1 is set.
Mtools only needs to be installed setuid if you use the
privileged or scsi drive variables. If you do not use these
options, mtools works perfectly well even when not installed
setuid root.
vold
Instructs mtools to interpret the device name as a vold
identifier rather than as a filename. The vold identifier is
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translated into a real filename using the media_findname() and
media_oldaliases() functions of the volmgt library. This flag is
only available if you configured mtools with the --enable-new-
vold option before compilation.
swap
Consider the media as a word-swapped Atari disk.
use_xdf
If this is set to a non-zero value, mtools also tries to access
this disk as an XDF disk. XDF is a high capacity format used by
OS/2. This is off by default. See section XDF, for more details.
mformat_only
Tells mtools to use the geometry for this drive only for
mformatting and not for filtering.
filter
Tells mtools to use the geometry for this drive both for
mformatting and filtering.
remote
Tells mtools to connect to floppyd (see section floppyd).
Supplying multiple descriptions for a drive
It is possible to supply multiple descriptions for a drive. In that
case, the descriptions are tried in order until one is found that
fits. Descriptions may fail for several reasons:
1. because the geometry is not appropriate,
2. because there is no disk in the drive,
3. or because of other problems.
Multiple definitions are useful when using physical devices which are
only able to support one single disk geometry. Example:
drive a: file="/dev/fd0H1440" 1.44m
drive a: file="/dev/fd0H720" 720k
This instructs mtools to use /dev/fd0H1440 for 1.44m (high density)
disks and /dev/fd0H720 for 720k (double density) disks. On Linux, this
feature is not really needed, as the /dev/fd0 device is able to handle
any geometry.
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You may also use multiple drive descriptions to access both of your
physical drives through one drive letter:
drive z: file="/dev/fd0"
drive z: file="/dev/fd1"
With this description, mdir z: accesses your first physical drive if
it contains a disk. If the first drive doesn't contain a disk, mtools
checks the second drive.
When using multiple configuration files, drive descriptions in the
files parsed last override descriptions for the same drive in earlier
files. In order to avoid this, use the drive+ or +drive keywords
instead of drive. The first adds a description to the end of the list
(i.e. it will be tried last), and the first adds it to the start of
the list.
Location of configuration files and parsing order
The configuration files are parsed in the following order:
1. compiled-in defaults
2. `/usr/local/etc/mtools.conf'
3. `~/.mtoolsrc'.
4. `$MTOOLSRC' (file pointed by the MTOOLSRC environmental variable)
Options described in the later files override those described in the
earlier files. Drives defined in earlier files persist if they are not
overridden in the later files. For instance, drives A and B may be
defined in `/usr/local/etc/mtools.conf' and drives C and D may be
defined in `~/.mtoolsrc' However, if `~/.mtoolsrc' also defines drive
A, this new description would override the description of drive A in
`/usr/local/etc/mtools.conf' instead of adding to it. If you want to
add a new description to a drive already described in an earlier file,
you need to use either the +drive or drive+ keyword.
Backwards compatibility with old configuration file syntax
The syntax described herein is new for version mtools-3.0. The old
line-oriented syntax is still supported. Each line beginning with a
single letter is considered to be a drive description using the old
syntax. Old style and new style drive sections may be mixed within the
same configuration file, in order to make upgrading easier. Support
for the old syntax will be phased out eventually, and in order to
discourage its use, I purposefully omit its description here.
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See also
mtools
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