MTOOLS

Section: Linux Programmer's Manual (5)
Updated: Dec 5, 1995
Index Return to Main Contents
 

NAME

mtools - table of DOS devices  

DESCRIPTION

/etc/mtools.conf and ~/.mtoolsrc are the configuration files for mtools. These configuration file describes the following items:

o
Global configuration flags and variables
o
Per drive flags and variables
o
Character translation tables

/etc/mtools.conf is the system-wide configuration file, and ~/.mtoolsrc is the user's private configuration file.

 

General 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. 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 variables may be set to 1 or to 0.

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.

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: export MTOOLS_SKIP_CHECK=1

 

PER DRIVE FLAGS AND VARIABLES

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.

 

General Purpose Drive Variables

The following variables are available:

file
The name of the file or device holding the disk image. This is mandatory. The file name should be enclosed in quotes. 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.
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 Syquests, ZIP drives, and DOSEMU hdimages. It is not recommended for hard disks to which direct access to partitions is available.
offset
Describes where in the file the MSDOS filesystem starts. This is useful for logical partitions in DOSEMU hdimages, and for ATARI ram disks. By default, this is zero, meaning that the filesystem start right at the beginning of the device or file.
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 autodetected number of fat bits wrong, or if you want to mformat a disk with a weird number of fat bits.

Only the file option is mandatory. The other parameters may be left out. In that case a default value or an autodetected value is used.

 

Drive Geometry Configuration

Geometry information describes the physical characteristics about the disk. Its has three purposes:

mformat
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 mformat(1) for details.
filtering
On some Unices there are device nodes which only support one physical geometry. 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 the next section "Supplying multiple descriptions for a drive" for more details on supplying several descriptions for a 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).

initial geometry
The geometry information (if available) is also used to set the initial geometry on configurable device nodes. This initial geometry is used to read the boot sector, which contains the real geometry. If no geometry information is supplied in the configuration file, no initial configuration is done. On Linux, this is not really needed either, as the configurable devices are able to autodetect the disk type 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 don't use geometry configuration unless you really need it.

The following geometry related variables are available:

cylinders
The number of cylinders.
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
	tracks=80 heads=2 sectors=18

The following shorthand geometry descriptions are available:

1.44m
high density 3 1/2 disk. Equivalent to: fat_bits=12 tracks=80 heads=2 sectors=18
1.2m
high density 5 1/4 disk. Equivalent to: fat_bits=12 tracks=80 heads=2 sectors=15
720k
double density 3 1/2 disk. Equivalent to: fat_bits=12 tracks=80 heads=2 sectors=9
360k
double density 5 1/4 disk. Equivalent to: fat_bits=12 tracks=40 heads=2 sectors=9

The shorthand format descriptions may be amended. For example, 360k sectors=8 describes a 320k disk and is equivalent to: fat_bits=12 tracks=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.

 

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.

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 (will be tried last), and the first adds it to the start of the list.

 

CHARACTER TRANSLATION TABLES

If you live in the USA, in Western Europe or in Australia, you may skip this section.

 

Introduction

DOS uses a different character code mapping than Unix. 7-bit characters still have the same meaning, only characters with the eight bit set are affected. To make matters worse, there are several translation tables available depending on the country where you are. The appearance of the characters is defined using code pages. These code pages aren't the same for all countries. For instance, some code pages don't contain upper case accented characters. On the other hand, some code pages contain characters which don't exist in Unix, such as certain line-drawing characters or accented consonants used by some Eastern European countries. This affects two things, relating to filenames:

upper case characters
In short names, only upper case characters are allowed. This also holds for accented characters. For instance, in a code page which doesn't contain accented uppercase characters, the accented lowercase characters get transformed into their unaccented counterparts.
long file names
Micro$oft has finally come to their senses and uses a more standard mapping for the long file names. They use Unicode, which is basically a 32 bit version of ASCII. Its first 256 characters are identical to Unix ASCII. Thus, the code page also affects the correspondence between the codes used in long names and those used in short names

Mtools considers the filenames entered on the command line as having the Unix mapping, and translates the characters to get short names. By default, code page 850 is used with the Swiss uppercase/lowercase mapping. I chose this code page, because its set of existing characters most closely matches Unix's. Moreover, this code page covers most characters in use in the USA, Australia and Western Europe. However, it is still possible to chose a different mapping. There are two methods: the country variable and explicit tables.

 

Configuration using Country

The COUNTRY variable is recommended for people which also have access to MSDOS system files and documentation. If you don't have access to these, I'd suggest you'd rather use explicit tables instead.

Syntax: COUNTRY=country[,[codepage],country.sys]

This tells mtools to use a Unix-to-DOS translation table which matches codepage and an lowercase-to-uppercase table for country and to use the country.sys file to get the lowercase-to-uppercase table. The country code is most often the telephone prefix of the country. Refer to the DOS help page on "country" for more details. The codepage and the country.sys parameters are optional. Please don't type in the square brackets, they are only there to say which parameters are optional. The country.sys file is supplied with MSDOS. In most cases you don't need it, as the most common translation tables are compiled into mtools. So, don't worry if you run a Unix-only box which lacks this file.

If codepage is not given, a per country default code page is used. If the country.sys parameter isn't given, compiled-in defaults are used for the lowercase-to-uppercase table. This is useful for other Unices than Linux, which may have no country.sys file available online.

The Unix-to-DOS are not contained in the country.sys file, and thus mtools always uses compiled-in defaults for those. Thus, only a limited amount of code pages are supported. If your preferred code page is missing, or if you know the name of the Windows 95 file which contains this mapping, could you please drop me a line at Alain.Knaff@inrialpes.fr .

The COUNTRY variable can also be set using the environment.

 

Configuration using explicit translation tables

Translation tables may be described in line in the configuration file. Two tables are needed: first the DOS-to-Unix table, and then the Lowercase-to-Uppercase table. A DOS-to-Unix table starts with the tounix keyword, followed by a colon, and 128 hexadecimal numbers. A lower-to-upper table starts with the fucase keyword, followed by a colon, and 128 hexadecimal numbers.

The tables only show the translations for characters whose codes is greater than 128, because translation for lower codes is trivial.

Example:

tounix:
	0xc7 0xfc 0xe9 0xe2 0xe4 0xe0 0xe5 0xe7 
	0xea 0xeb 0xe8 0xef 0xee 0xec 0xc4 0xc5 
	0xc9 0xe6 0xc6 0xf4 0xf6 0xf2 0xfb 0xf9 
	0xff 0xd6 0xdc 0xf8 0xa3 0xd8 0xd7 0x5f 
	0xe1 0xed 0xf3 0xfa 0xf1 0xd1 0xaa 0xba 
	0xbf 0xae 0xac 0xbd 0xbc 0xa1 0xab 0xbb 
	0x5f 0x5f 0x5f 0x5f 0x5f 0xc1 0xc2 0xc0 
	0xa9 0x5f 0x5f 0x5f 0x5f 0xa2 0xa5 0xac 
	0x5f 0x5f 0x5f 0x5f 0x5f 0x5f 0xe3 0xc3 
	0x5f 0x5f 0x5f 0x5f 0x5f 0x5f 0x5f 0xa4 
	0xf0 0xd0 0xc9 0xcb 0xc8 0x69 0xcd 0xce 
	0xcf 0x5f 0x5f 0x5f 0x5f 0x7c 0x49 0x5f 
	0xd3 0xdf 0xd4 0xd2 0xf5 0xd5 0xb5 0xfe 
	0xde 0xda 0xd9 0xfd 0xdd 0xde 0xaf 0xb4 
	0xad 0xb1 0x5f 0xbe 0xb6 0xa7 0xf7 0xb8 
	0xb0 0xa8 0xb7 0xb9 0xb3 0xb2 0x5f 0x5f 

fucase:
	0x80 0x9a 0x90 0xb6 0x8e 0xb7 0x8f 0x80 
	0xd2 0xd3 0xd4 0xd8 0xd7 0xde 0x8e 0x8f 
	0x90 0x92 0x92 0xe2 0x99 0xe3 0xea 0xeb 
	0x59 0x99 0x9a 0x9d 0x9c 0x9d 0x9e 0x9f 
	0xb5 0xd6 0xe0 0xe9 0xa5 0xa5 0xa6 0xa7 
	0xa8 0xa9 0xaa 0xab 0xac 0xad 0xae 0xaf 
	0xb0 0xb1 0xb2 0xb3 0xb4 0xb5 0xb6 0xb7 
	0xb8 0xb9 0xba 0xbb 0xbc 0xbd 0xbe 0xbf 
	0xc0 0xc1 0xc2 0xc3 0xc4 0xc5 0xc7 0xc7 
	0xc8 0xc9 0xca 0xcb 0xcc 0xcd 0xce 0xcf 
	0xd1 0xd1 0xd2 0xd3 0xd4 0x49 0xd6 0xd7 
	0xd8 0xd9 0xda 0xdb 0xdc 0xdd 0xde 0xdf 
	0xe0 0xe1 0xe2 0xe3 0xe5 0xe5 0xe6 0xe8 
	0xe8 0xe9 0xea 0xeb 0xed 0xed 0xee 0xef 
	0xf0 0xf1 0xf2 0xf3 0xf4 0xf5 0xf6 0xf7 
	0xf8 0xf9 0xfa 0xfb 0xfc 0xfd 0xfe 0xff 

The first table maps DOS character codes to Unix character codes. For example, the DOS character number 129. This is a u with to dots on top of it. To translate it into Unix, we look at the character number 1 in the first table (1 = 129 - 128). This is 0xfc. (Beware, numbering starts at 0). The second table maps lower case DOS characters to upper case DOS characters. The same lower case u with dots maps to character 0x9a, which is an uppercase U with dots in DOS.

 

Unicode characters greater than 256

If an existing MSDOS name contains Unicode character greater than 256, these are translated to underscores or to characters which are close in visual appearance. For example, accented consonants are translated into their unaccented counterparts. This translation is used for mdir and for the Unix filenames generated by mcopy. Linux does support Unicode too, but unfortunately too few applications support it yet to bother with it in mtools. Most importantly, xterm can't display Unicode yet. If there is sufficient demand, I might include support for Unicode in the Unix filenames as well.

Caution: When deleting files with mtools, the underscore matches all characters which can't be represented in Unix. Be careful before mdel!

 

LOCATION OF CONFIGURATION FILES AND PARSING ORDER

The configuration files are parsed in the following order:

1
compiled-in defaults
2
/etc/mtools.conf
3
/etc/mtools This is for backwards compatibility only, and is only parsed if mtools.conf doesn't exist.
4
~/.mtoolsrc.

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 /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 /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

The syntax described herein is new for version mtools-2.5.4. 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.

 

FILES

/etc/mtools.conf, ~/.mtoolsrc  

SEE ALSO

mtools(1)


 

Index

NAME
DESCRIPTION
General Syntax
Default values
GLOBAL VARIABLES
PER DRIVE FLAGS AND VARIABLES
General Purpose Drive Variables
Drive Geometry Configuration
Open Flags
Supplying multiple descriptions for a drive
CHARACTER TRANSLATION TABLES
Introduction
Configuration using Country
Configuration using explicit translation tables
Unicode characters greater than 256
LOCATION OF CONFIGURATION FILES AND PARSING ORDER
BACKWARDS COMPATIBILITY
FILES
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 15:58:54 GMT, November 05, 2024