Special features in ST-DOS

1. Creating filesystem images

ST-DOS does not have a DISKCOPY command. You can create an image file from
a filesystem, for example from a floppy drive, simply by just using the COPY
command. The special file name for mounted filesystems is DRV:l, where l is
the letter of the drive. For example, if you want to create an image file
FLOPPY.DSK from the floppy disk that is in the drive A, type the following
command:

  COPY DRV:A FLOPPY.DSK

This can be used to create exact copies of floppy disks. If you want to write
the contents of the image file FLOPPY.DSK to a floppy disk that is in the
drive A, type the following command:

  COPY FLOPPY.DSK DRV:A

Notice that before writing an image file to a floppy that has a different
geometry, you need to first write the correct physical geometry to the disk
using the FORMAT.COM program.

If you want to create an "empty" filesystem image, you can use the FORMAT.COM
program to do that. Specify a file name as the target instead of a drive
letter. For example, if you want to create an empty image file EMPTY.DSK that
resembles a 720 kB floppy disk, type the following command:

  FORMAT EMPTY.DSK /SIZE=720

2. Mounting filesystem images

Filesystem images can be mounted by using the MOUNT.COM program. A mounted
filesystem image can be used like any normal filesystem. The only limitation
is that you cannot mount filesystem images inside a filesystem that is
mounted from an image file, to protect the kernel stack from overflowing.

If you want to mount a FAT12 image file IMAGE.DSK, type the following
command:

  MOUNT IMAGE.DSK B: 1

If you want to mount a .ISO image, the CD-ROM drivers must be loaded. You
can then mount the image by typing the following command:

  MOUNT IMAGE.ISO B: 128 ISO


3. Toggle verify flag on/off

You can toggle the verify flag on or off by typing VERIFY 1 or VERIFY 0
to the command line. Without arguments the VERIFY command shows the current
status of the verify flag.

4. Changing the size of file buffers

The maximum size of file buffers can be changed by typing BUFFERS $bytecount,
where $bytecount is the maximum count of octets in a write buffer. The
default value is 65535. The BUFFERS command without arguments shows the
current value.

5. Creating a bootable disk (replicating the system)

After formatting a drive with the FORMAT.COM program, you can use the SYS.COM
program to transfer the boot code to the target filesystem. Notice that you
need to have the BOOTCODE.086 file in the current working directory when
SYS.COM is executed. SYS.COM doesn't copy the kernel to the target
filesystem. You have to do it manually.