3.5.5 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) 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

precmd

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.

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.